• I would not assume cooling has been worked out.

    Space is a vacuum. i.e. The lack-of-a-thing that makes a thermos great at keeping your drink hot. A satellite is, if nothing else, a fantastic thermos. A data center in space would necessarily rely completely on cooling by radiation, unlike a terrestrial data center that can make use of convection and conduction. You can't just pipe heat out into the atmosphere or build a heat exchanger. You can't exchange heat with vacuum. You can only radiate heat into it.

    Heat is going to limit the compute that can be done in a satellite data centre and radiative cooling solutions are going to massively increase weight. It makes far more sense to build data centers in the arctic.

    Musk is up to something here. This could be another hyperloop (i.e. A distracting promise meant to sabotage competition). It could be a legal dodge. It could be a power grab. What it will not be is a useful source of computing power. Anyone who takes this venture seriously is probably going to be burned.

    • It's exiting the 5th best social network and the 10th (or worse) best AI company and selling them to a decent company.

      It probably increases Elon's share of the combined entity.

      It delivers on a promise to investors that he will make money for them, even as the underlying businesses are lousy.

      • gpt5
        I'm confused about the level of conversation here. Can we actually run the math on heat dissipation and feasibility?

        A Starlink satellite uses about 5K Watts of solar power. It needs to dissipate around that amount (+ the sun power on it) just to operate. There are around 10K starlink satellites already in orbit, which means that the Starlink constellation is already effectively equivalent to a 50 Mega-watt (in a rough, back of the envelope feasibility way).

        Isn't 50MW already by itself equivalent to the energy consumption of a typical hyperscaler cloud?

        Why is starlink possible and other computations are not? Starlink is also already financially viable. Wouldn't it also become significantly cheaper as we improve our orbital launch vehicles?

        • Output from radiating heat scales with area it can dissipate from. Lots of small satellites have a much higher ratio than fewer larger satellites. Cooling 10k separate objects is orders of magnitude easier than 10 objects at 1000x the power use, even if the total power output is the same.

          Distributing useful work over so many small objects is a very hard problem, and not even shown to be possible at useful scales for many of the things AI datacenters are doing today. And that's with direct cables - using wireless communication means even less bandwidth between nodes, more noise as the number of nodes grows, and significantly higher power use and complexity for the communication in the first place.

          Building data centres in the middle of the sahara desert is still much better in pretty much every metric than in space, be it price, performance, maintainance, efficiency, ease of cooling, pollution/"trash" disposal etc. Even things like communication network connectivity would be easier, as at the amounts of money this constellation mesh would cost you could lay new fibre optic cables to build an entire new global network to anywhere on earth and have new trunk connections to every major hub.

          There are advantages to being in space - normally around increased visibility for wireless signals, allowing great distances to be covered at (relatively) low bandwidth. But that comes at an extreme cost. Paying that cost for a use case that simply doesn't get much advantages from those benefits is nonsense.

          • Why would they bother to build space data center in such monolithic massive structures at all? Direct cables between semi-independent units the size of a star link v2 satellite. That satellite size is large enough to encompass a typical 42U server rack even without much physical reconfiguration. It doesn't need to be "warehouse sized building, but in space", and neither does it have to be countless objects kilometers apart from each other beaming data wirelessly. A few dozen wired as a cluster is much more than sufficient to avoid incurring any more bandwidth penalties on server-to-server communication with correlated work loads than we already have on earth for most needs.

            Of course this doesn't solve the myriad problems, but it does put dissipation squarely in the category of "we've solved similar problems". I agree there's still no good reason to actually do this unless there's a use for all that compute out there in orbit, but that too is happening with immense growth and demand expected for increased pharmaceutical research and various manufacturing capabilities that require low/no gravity.

            • Not just a 42U rack, but a 42U rack that needs one hundred thousand watts of power, and it also needs to be able to remove one hundred thousand watts of heat out of the rack, and then it needs to dump that one hundred thousand watts of heat into space.
          • > using wireless communication means even less bandwidth between nodes, more noise as the number of nodes grows, and significantly higher power use

            Space changes this. Laser based optical links offer bandwidth of 100 - 1000 Gbps with much lower power consumption than radio based links. They are more feasible in orbit due to the lack of interference and fogging.

            > Building data centres in the middle of the sahara desert is still much better in pretty much every metric

            This is not true for the power generation aspect (which is the main motivation for orbital TPUs). Desert solar is a hard problem due to the need for a water supply to keep the panels clear of dust. Also the cooling problem is greatly exacerbated.

            • You don’t need to do anything to keep panels with a significant angle clear of dust in deserts. The Sahara is near the equator but you can stow panels at night and let the wind do its thing.

              The lack of launch costs more than offset the need for extra panels and batteries.

              • What’s your source for that claim? Soiling is a massive problem for desert solar, causing as high as 50% efficiency loss in the Middle East.[1]

                [1] https://www.nlr.gov/news/detail/features/2021/scientists-stu...

                • A relevant quote from that article.

                  “The reason I concentrate my research on these urban environments is because the composition of soiling is completely different,” said Toth, a Ph.D. candidate in environmental engineering at the University of Colorado who has worked at NREL since 2017. “We have more fine particles that are these stickier particles that could contribute to much different surface chemistry on the module and different soiling. In the desert, you don’t have as much of the surface chemistry come into play.”

            • Space doesn't really change it though because the effective bandwidth between nodes is reduced by the overall size of the network and how much data they need to relay between each other.
              • Yup. We don't use fibre optics on earth rather than lasers because of some specific limitation of the earth's surface being in orbit would avoid.

                We use them because they're many orders of magnitude cheaper and simpler for anywhere near the same bandwidth for the distances required.

          • Whatever sat datacenter they biuld, it would run better/easier/faster/cheaper sitting on the ground in antarctica than it would in space, or floating on the ocean, without the launch costs. Space is useful for those activities that can only be done from space. For general computing? Not until all the empty parts of the globe are full.

            This is a pump-and-dump bid for investor money. They will line up to give it to him.

            • Yup - my example of the Sahara wasn't really a specific suggestion, so much as an example of "The Most Inconvenient Inhospitable part of the earth's surface is still much better than space for these use cases". This isn't star trek, the world doesn't match sci-fi.

              It's like his "Mars Colony" junk - and people lap it up, keeping him in the news (in a not explicitly negative light - unlike some recent stories....)

            • > Whatever sat datacenter they biuld, it will run better/easier/faster/cheaper sitting on the ground in antarctica than it will in space

              That is clearly not true. How do you power the data center on antarctica? May i remind you it will be in the shadow of earth for half a year.

              • A tanker full of LNG and a turbine would probably work.
                • Kinda like the ones they are already burning in Starship to put these in space in the first place.

                  Anywhere on earth is better than space for this application.

              • > How do you power the data center on antarctica?

                Nuclear power plant?

              • Space is so expensive that you can power it pretty much any way you want and it will be cheaper. Nuclear reactor, LNG, batteries (truck them in and out if you have to). Hell, space based solar and beam it down. Why would there ever be an advantage to putting the compute in space?
                • Get those penguins doing something productive for once, put them on treadmills!
                  • Or burn them in a furnace. Pretty much any way you can think of to accomplish something on earth, is vastly cheaper, easier, and faster than doing it in space.
              • Then you put another in the high north. Two, or six, is still cheaper than one in orbit.
        • Simply put no, 50MW is not the typical hyperscaler cloud size. It's not even the typical single datacenter size.

          A single AI rack consumes 60kW, and there is apparently a single DC that alone consumes 650MW.

          When Microsoft puts in a DC, the machines are done in units of a "stamp", ie a couple racks together. These aren't scaled by dollar or sqft, but by the MW.

          And on top of that... That's a bunch of satellites not even trying to crunch data at top speed. No where near the right order of magnitude.

          • But the focus on building giant monolithic datacenters comes from the practicalities of ground based construction. There are huge overheads involved with obtaining permits, grid connections, leveling land, pouring concrete foundations, building roads and increasingly often now, building a power plant on site. So it makes sense to amortize these overheads by building massive facilities, which is why they get so big.

            That doesn't mean you need a gigawatt of power before achieving anything useful. For training, maybe, but not for inference which scales horizontally.

            With satellites you need an orbital slot and launch time, and I honestly don't know how hard it is to get those, but space is pretty big and the only reasons for denying them would be safety. Once those are obtained done you can make satellite inferencing cubes in a factory and just keep launching them on a cadence.

            I also strongly suspect, given some background reading, that radiator tech is very far from optimized. Most stuff we put into space so far just doesn't have big cooling needs, so there wasn't a market for advanced space radiator tech. If now there is, there's probably a lot of low hanging fruit (droplet radiators maybe).

            • But why would you?

              Space has some huge downsides:

              * Everything is being irradiated all the time. Things need to be radiation hardened or shielded.

              * Putting even 1kg into space takes vast amounts of energy. A Falcon 9 burns 260 MJ of fuel per kg into LEO. I imagine the embodied energy in the disposable rocket and liquid oxygen make the total number 2-3x that at least.

              * Cooling is a nightmare. The side of the satellite in the sun is very hot, while the side facing space is incredibly cold. No fans or heat sinks - all the heat has to be conducted from the electronics and radiated into space.

              * Orbit keeping requires continuous effort. You need some sort of hypergolic rocket, which has the nasty effect of coating all your stuff in horrible corrosive chemicals

              * You can't fix anything. Even a tiny failure means writing off the entire system.

              * Everything has to be able to operate in a vacuum. No electrolytic capacitors for you!

              So I guess the question is - why bother? The only benefit I can think of is very short "days" and "nights" - so you don't need as much solar or as big a battery to power the thing. But that benefit is surely outweighed by the fact you have to blast it all into space? Why not just overbuild the solar and batteries on earth?

              • The main reason is that generating energy in space is very cheap and easy due to how ridiculously effective solar panels are.

                Someone mentioned in the comments on a similar article that sun synchronous orbits are a thing. This was a new one to me. Apparently there's a trick that takes advantage of the Earth not being a perfect sphere to cause an orbit to precess at the right rate that it matches the Earth's orbit around the sun. So, you can put a satellite into a low-Earth orbit that has continuous sunlight.

                https://en.wikipedia.org/wiki/Sun-synchronous_orbit

                Is this worth all the cost and complexity of lobbing a bunch of data centers into orbit? I have no idea. If electricity costs are what's dominating the datacenter costs that AI companies are currently paying, then I'm willing to at least concede that it might be plausible.

                If I were being asked to invest in this scheme, I would want to hear a convincing argument why just deploying more solar panels and batteries on Earth to get cheap power isn't a better solution. But since it's not my money, then if Elon is convinced that this is a great idea then he's welcome to prove that he (or more importantly, the people who work for him) have actually got this figured out.

                • Let's assume your space solar panel is always in sun - so 8760 kWh per year from 1kWp.

                  In Spain, 1kWp of solar can expect to generate about 1800 kWh per year. There's a complication because seasonal difference is quite large - if we assume worst case generation (ie what happens in December), we get more like 65% of that, or 1170 kWh per year.

                  That means we need to overbuild our solar generation by about 7.5x to get the same amount of generation per year. Or 7.5kWp.

                  We then need some storage, because that generation shuts off at night. In December in Madrid the shortest day is about 9 hours, so we need 15 hours of storage. Assuming a 1kW load, that means 15kWh.

                  European wholesale solar panels are about €0.1/W - €100/kW. So our 7.5kWp is €750. A conservative estimate for batteries is €100/kWh. So our 15kWh is €1500. There's obviously other costs - inverters etc. But perhaps the total hardware cost is €3k for 1kW of off-grid solar.

                  A communications satellite like the Eurostar Neo satellite has a payload power of 22 kW and a launch mass of 4,500 kg. Assuming that's a reasonable assumption, that means about 204kg per kW. Current SpaceX launch costs are circa $1500 per kg - but they're targeting $100/kg or lower. That would give a launch cost of between $300k and $20k per kW of satellite power. That doesn't include the actual cost of the satellite itself - just the launch.

                  I just don't see how it will make sense for a long time. Even if SpaceX manage to drastically lower launch costs. Battery and solar costs have also been plummeting.

                  https://www.spaceconnectonline.com.au/manufacturing/4751-air...

                  https://www.nextbigfuture.com/2025/01/spacex-starship-roadma...

                  • Thanks for the interesting calculations.

                    Is it reasonable to use Neo as a baseline? Modern Starlink satellites can weigh 800kg, or less than 20% of Neo. I see discussions suggesting they generate ~73kw for that mass. I guess because they aren't trying to blanket an entire continent in signal? Or, why are they so much more efficient than Neo?

                    Interestingly the idea of doing compute in space isn't a new one, it came up a few years ago pre-ChatGPT amongst people discussing the v2 satellite:

                    https://forum.nasaspaceflight.com/index.php?topic=58374.msg2...

                    Still, you make good points. Even if you assume much lighter satellites, the GPUs alone are very heavy. 700kg or so for a rack. Just the payload would be as heavy as the entire Starlink satellite.

                • Kind of a scary thought - a DC in space can't be stopped by protests or regulation
              • > So I guess the question is - why bother?

                This is a Musk escapade, so my guess would be extraterritoriality and absence of jurisdiction.

                • No. With Musk it is always about inflating his share prices.
              • If one kilogram of stuff consumes just 100Wt, then in one month it consumes about 300 MJ. So as long as things works for a year or more energy cost to put them into orbit becomes irrelevant.

                To keep things in orbit ion thrusters work nicely and require just inert gases to keep them functioning. Plus on a low Earth orbit there are suggestions that a ramjet that capture few atoms of atmosphere and accelerates them could work.

                Radiative cooling scales by 4th power temperature. So if one can design electronics to run at, say, 100 C, then calling would be much less problematic.

                But radiation is the real problem. Dealing with that would require entirely different architecture/design.

              • It would make more sense to develop power beaming technology. Use the knowledge from Starlink constellations to beam solar power via microwaves onto the rooftops of data centers
                • Hello SimCity 2000 Microwave Power Plant.
                  • Looking forward to an CNN breaking chyron titled "Oops!"
                • Why? We have solar panels and fossil fuels at home.
                • Why does that make sense at all
                  • > Why does that make sense at all

                    Parent said it would make more sense.

                    I guess in terms of the relative level of stupidity on display, it would be slightly less stupid to build huge reflectors in space than it is to try to build space datacenters, where the electricity can only power specific pieces of equipment that are virtually impossible to maintain (and are typically obsolete within a few years).

                • Everybody wants a death ray.
              • Maybe they should try to build it in the moon. Difficult, but perhaps not as difficult?
                • Almost none of the parent’s bullet points are solved by building on the Moon instead of in Earth orbit.

                  The energy demands of getting to the 240k mile Moon are IMMENSE compared to 100 mile orbit.

                  Ultimately, when comparing the 3 general locations, Earth is still BY FAR the most hospitable and affordable location until some manufacturing innovations drop costs by orders of magnitude. But those manufacturing improvements have to be made in the same jurisdiction that SpaceXAI is trying to avoid building data centers in.

                  This whole things screams a solution in search of a problem. We have to solve the traditional data center issues (power supply, temperature, hazard resilience, etc) wherever the data centers are, whether on the ground or in space. None of these are solved for the theoretical space data centers, but they are all already solved for terrestrial data centers.

                  • In situ iron, titanium, aluminum?
                    • But none of those are usable, right? It will take decades of work at least to get a commercial grade mining operation going and even then the iron, titanium, aluminum would need to be fashioned...

                      Ah, I see the idea now. It is to get people to talk about robotics and how robots will be able to do all this on the moon or wherever.

                      Instantly pumps Tesla stock here now on earth!

                    • That's a hard problem to solve. Invest enough in solving that problem and you might get the ability to manufacture a radiator out of it, but you're still going to have to transport the majority of your datacenter to the moon. That probably works out more expensive than launching the whole thing to LEO
                • Sounds more difficult. Not only is the moon further, you also need to use more fuel to land on it and you also have fine, abrasive dust to deal with. There’s no wind of course, but surely material will be stirred up and resettle based on all the landing activity.

                  And it’s still a vacuum with many of the same cooling issues. I suppose one upside is you could use the moon itself as a heat sink (maybe).

                  • > Not only is the moon further, you also need to use more fuel to land on it

                    And take off again, if reusable spacecraft are meant to be used.

                • The 2.5s round trip communication latency isn't going to be great for chat. (Alongside all the other reasons.)
                  • And 2.5s is best case. Signal strength issues, antenna alignment issues, and all sorts of unknown unknowns conspire to make high-integrity/high-throughput digital signal transmissions from a moon-based compute system have a latency much worse than that on average.
                • Still a vacuum so the same heat dissipation issues, adding to it that the lunar dust makes solar panels less usable, and the lunar surface on the solar side gets really hot.
                • It has all these problems, plus more.
                • Yeah, carrying stuff 380k km and still deploying in vacuum (and super dusty ground) doesn't solve anything but adds cost and overhead. One day maybe, but not these next decades nor probably this century.
              • "But why would you?"

                Because the permitting process is much easier and there are way, way fewer authorities that can potentially shut you down.

                I think this is the entire difference. Space is very, very lightly regulated, especially when it comes to labor, construction and environmental law. You need to be able to launch from somewhere and you need to automate a lot of things. But once you can do this, you escaped all but a few authorities that would hold power over you down on Earth.

                No one will be able to complain that your data center is taking their water or making their electricity more expensive, for example.

                • The satellite is built on Earth, so I’m not sure how it dodges any of those regulations practically. Why not just build a fully autonomous, solar powered datacenter on Earth? I guess in space Elon might think that no one can ban Grok for distributing CSAM?

                  There’s some truly magical thinking behind the idea that government regulations have somehow made it cheaper to launch a rocket than build a building. Rockets are fantastically expensive even with the major leaps SpaceX made and will be even with Starship. Everything about a space launch is expensive, dangerous, and highly regulated. Your datacenter on Earth can’t go boom.

                  • Truly magical thinking, you say? OK, let's rewind the clock to 2008. In that year two things happened:

                    - SpaceX launched its first rocket successfully.

                    - California voted to build high speed rail.

                    Eighteen years later:

                    - SpaceX has taken over the space industry with reusable rockets and a global satcom network, which by itself contains more than half of all satellites in orbit.

                    - Californian HSR has spent over thirteen billion dollars and laid zero miles of track. That's more than 2x the cost of the Starship programme so far.

                    Building stuff on Earth can be difficult. People live there, they have opinions and power. Their governments can be dysfunctional. Trains are 19th century technology, it should be easier to build a railway than a global satellite network. It may seem truly magical but putting things into orbit can, apparently, be easier.

                    • it should be easier to build a railway

                      No, because of the costs of acquiring land that the railway goes through.

                      • Now how about procuring half a gigawatt when nearby residents are annoyed about their heating bills doubling, and are highly motivated to block you? This is already happening in some areas.
                  • "fantastically expensive"

                    From individual POV yes, but already Falcons are not that expensive. In the sense that it is feasible for a relatively unimportant entity to buy their launch services.

                    "The satellite is built on Earth, so I’m not sure how it dodges any of those regulations practically."

                    It is easier to shop for jurisdiction when it comes to manufacturing, especially if your design is simple enough - which it has to be in order to run unattended for years. If you outsource the manufacturing to N chosen factories in different locations, you can always respond to local pressure by moving out of that particular country. In effect, you just rent time and services of a factory that can produce tons of other products.

                    A data center is much more expensive to build and move around. Once you build it in some location, you are committed quite seriously to staying there.

                • So it's a Zone in search of a use case?
                • Libertarian Paradise!

                  Too bad the fire trucks can't get to you when you catch on fire from that hot GPU.

                  • Good thing the lack of oxygen does a pretty good job of taking care of that for you ;-)
            • > I also strongly suspect, given some background reading, that radiator tech is very far from optimized. Most stuff we put into space so far just doesn't have big cooling needs, so there wasn't a market for advanced space radiator tech. If now there is, there's probably a lot of low hanging fruit (droplet radiators maybe).

              You'd be wrong. There's a huge incentive to optimized radiator tech because of things like the international space station and MIR. It's a huge part of the deployment due to life having pretty narrow thermal bands. The added cost to deploy that tech also incentivizes hyper optimization.

              Making bigger structures doesn't make that problem easier.

              Fun fact, heat pipes were invented by NASA in the 60s to help address this very problem.

              • ISS and MIR combined are not a "large market". How many radiators they require? Probably a single space dc will demand a whole orders of magnitude more cooling
                • ISS cost $150B and a large factor driving that cost was the payload weight.

                  Minimizing payload at any point was easily worth a billion dollars. And given how heavy and nessisary the radiators are (look them up), you can bet a decent bit of research was invested in making them lightweight.

                  Heck, one bit of research that lasted the entire lifetime of the shuttle was improving the radiative heat system [1]. Multiple contractors and agencies invested a huge amount of money to make that system better.

                  Removing heat is one of the most researched problems of all space programs. They all have to do it, and every gram of reduction means big savings. Simply saying "well a DC will need more of it, therefore there must be low hanging fruit" is naive.

                  [1] https://llis.nasa.gov/lesson/6116

              • The ISS is a government project that's heading towards EOL, it has no incentive to heavily optimize anything because the people who built it don't get rich by doing so. SpaceX is what optimization looks like, not the ISS.
                • > has no incentive to heavily optimize anything because the people who built it don't get rich by doing so.

                  Optimization is literally how contractors working for the government got rich. Every hour they spent on research was directly billed to the government. Weight reduction being one of the most important and consistent points of research.

                  Heck, R&D is how some of the biggest government contractors make all their dough.

                  SpaceX is built on the billions in research NASA has invested over the decades. It looks like it's more innovative simply because the USG decided to nearly completely defund public spending in favor of spending money on private contractors like SpaceX. That's been happening since the 90s.

                • By the same token SpaceX has no reason to optimize Starship. That is also largely a government project.
                  • b112
                    It's a private company, is profit motivated, and thus has reason to optimize. That was the parent poster's point.

                    Starship isn't largely a government project. It was planned a decade before the government was ever involved, they came along later and said "Hey, this even more incredible launch platform you're building? Maybe we can hire SpaceX to launch some things with it?"

                    Realistically, SpaceX launches far more payload than any government.

                    • Lockheed, Boeing, Northrop, Raytheon, and all the others are private companies, too. NASA and others generally go through contractors to build things. SpaceX is on the dole just like them.
                    • Haha no. SpaceX survives entirely on money from the US government. It's always been that way.
                      • Where are you getting this from?
                      • Entirely? lol not even close.

                        Source: I am out of LEDs and LASERs and now handle aerospace solar for a private company. Guess who almost everyone in the private sector flies on?

                      • A puzzling statement, could you explain? Most of their revenue now comes Starlink which is mostly private clients. Also it's trivial to look at their launch history and see they have plenty of private clients. For sure the USG is their most important client but "entirely" is flat out wrong.
                  • that is true. They would have failed after their first failed launch. The US government saved them.
            • There is a lot of hand waiving away of the orders of magnitude more manufacturing, more launches, and more satellites that have to navigate around each other.

              We still don’t have any plan I’ve heard of for avoiding a cascade of space debris when satellites collide and turn into lots of fast moving shrapnel. Yes, space is big, but low Earth orbit is a very tiny subset of all space.

              The amount of propulsion satellites have before they become unable to maneuver is relatively small and the more satellite traffic there is, the faster each satellite will exhaust their propulsion gasses.

              • > We still don’t have any plan I’ve heard of for avoiding a cascade of space debris when satellites collide and turn into lots of fast moving shrapnel.

                What do you mean we don’t have any plans to avoid that? It is a super well studied topic of satelite management. Full books have been written on the topic.

                Here is just one: https://ntrs.nasa.gov/api/citations/20230002470/downloads/CA...

                Did you think satelites are kept apart by good luck and providence?

              • >There is a lot of hand waiving away of the orders of magnitude more manufacturing, more launches, and more satellites that have to navigate around each other.

                This is exactly like the Boring Company plans to "speed up" boring. Lots of hand waving away decades of commercial boring, sure that their "great minds" can do 10x or 100x better than modern commercial applications. Elon probably said "they could just run the machines faster! I'm brilliant".

            • All of those “huge overheads” you cite are nothing compared to the huge overhead of building and fueling rockets to launch the vibration- and radiation-hardened versions of the solar panels and GPUs and cooling equipment that you could use much cheaper versions of on Earth. How many permitted, regulated launches would it take to get around the one-time permitting and predictable regulation of a ground-based datacenter?

              Are Earth-based datacenters actually bound by some bottleneck that space-based datacenters would not be? Grid connections or on-site power plants take time to build, yes. How long does it take to build the rocket fleet required to launch a space “datacenter” in a reasonable time window?

              This is not a problem that needs to be solved. Certainly not worth investing billions in, and definitely not when run by the biggest scam artist of the 21st century.

          • pera
            New GPU dense racks are going up to 300kW, but I believe the normal at moment for hyperscalers is somewhere around ~150kW, can someone confirm?

            The energy demand of these DCs is monstrous, I seriously can't imagine something similar being deployed in orbit...

            • Most of the OEMs are past 300kW racks, planning on 600kW racks within a year or two, with realistic plans to hit a megawatt
            • Could this be about bypassing government regulation and taxation? Silkroad only needed a tiny server, not 150kW.

              The Outer Space Treaty (1967) has a loophole. If you launch from international waters (planned by SpaceX) and the equipment is not owned by a US-company or other legal entity there is significant legal ambiguity. This is Dogecoin with AI. Exploiting this accountability gap and creating a Grok AI plus free-speech platform in space sounds like a typical Elon endeavour.

              • For the sake of an argument, let’s assume "The Outer Space Treaty (1967) has a loophole. If you launch from international waters (planned by SpaceX) and the equipment is not owned by a US-company or other legal entity there is significant legal ambiguity” is 100% true.

                To use that loophole, the rockets launched by SpaceX would have to be “not owned by a US-company”. Do you think the US government would allow that to happen?

              • Untrue. Responsible for any spacefaring vessel is in all cases the state the entity operating the vessel is registered in. If it's not SpaceX directly but a shell company in Ecuador carrying out the launch, Ecuador will be completely responsible for anything happening with and around the vessel, period. There are no loopholes in this system.
              • This could simply be done by hosting in the Tor hidden service cloud. Accessing illegal material hosted on a satellite is still exactly as risky for the user (if the user is on earth) as accessing that same illegal material through the Tor network, but hosting it through the Tor network can be done for 1/1000th the cost compared to an orbital solution.

                So there's no regulatory or tax benefit to hosting in space.

              • You cannot escape national regulations like that, at least until a maritime-like situation develops, where rockets will be registered in Liberia for a few dollars and Liberia will not even pretend to care what they are doing.

                It may happen one day, but we are very, very far from that. As of now, big countries watch their space corporations very closely and won't let them do this.

                Nevertheless, as an American, you can escape state and regional authorities this way. IIRC The Californian Coastal Commission voted against expansion of SpaceX activities from Vandenberg [1], and even in Texas, which is more SpaceX-friendly, there are still regulations to comply with.

                If you launch from international waters, these lower authority tiers do not apply.

                [1] https://www.latimes.com/business/story/2025-08-14/california...

              • In addition to all the sibling comments explaining why this wouldn't work, the money's not there.

                A grift the size of Dogecoin, or the size of "free speech" enthusiast computing, or even the size of the criminal enterprises that run on the dark web, is tiny in comparison to the footer cost and upkeep of a datacenter in space. It'd also need to be funded by investments (since criminal funds and crypto assets are quite famously not available in up-front volumes for a huge enterprise), which implies a market presence in some country's economy, which implies regulators and risk management, and so on.

              • No. There is no "one weird trick" when it comes to regulation. The company is based in the US, therefore you just go after that.

                Anyway, promising some fantasy and never delivering is definitely a typical Elon endeavor.

              • You misspelled 'hate speech'.
          • How much of that power is radiated as the radio waves it sends?
            • Good point - the comms satellites are not even "keeping" some of the energy, while a DC would. I _am_ now curious about the connection between bandwidth and wattage, but I'm willing to bet that less than 1% of the total energy dissipation on one of these DC satellites would be in the form of satellite-to-earth broadcast (keeping in mind that s2s broadcast would presumably be something of a wash).
              • I am willing to bet that more than 10% of the electrical energy consumed by the satellite is converted into transmitted microwaves.

                There must be many power consumers in the satellite, e.g. radio receivers, lasers, computers and motors, where the consumed energy eventually is converted into heat, but the radio transmitter of a communication satellite must take a big fraction of the average consumed power.

                The radio transmitter itself has a great efficiency, much greater than 50%, possibly greater than 90%, so only a small fraction of the electrical power consumed by the transmitter is converted into heat and most is radiated in the microwave signal that goes to Earth's surface.

                • Unfortunately this is not the case. The amplifiers on the transmit-side phased arrays are about 10% efficient (perhaps 12% on a good day), but the amps represent only ~half the power consumption of the transmit phased arrays. The beamformers and processors are 0% efficient. The receive-side phased arrays are of course 0% efficient as well.
                  • I'm curious. I think the whole thing (space-based compute) is infeasible and stupid for a bunch of reasons, but even a class-A amplifier has a theoretical limit of 50% efficiency, and I thought we used class-C amplifiers (with practical efficiencies above 50%) in FM/FSK/etc. applications in which amplitude distortion can be filtered away. What makes these systems be down at 10%?
                    • Yes, a 10% efficiency is very weird if true.

                      Nowadays such microwave power amplifiers should be made with gallium nitride transistors, which should allow better efficiencies than the ancient amplifiers using LDMOS or travelling-wave tubes, and even those had efficiencies over 50%.

                      For beamformers, there have been research papers in recent years claiming a great reduction in losses, but presumably the Starlink satellites are still using some mature technology, with greater losses.

            • I doubt half the power is to the transmitter, and radio efficiency is poor -- 20% might be a good starting point.
              • Is the SpaceX thin-foil cooling based on graphene real? Can experts check this out?

                "SmartIR’s graphene-based radiator launches on SpaceX Falcon 9" [1]. This could be the magic behind this bet on heat radiation through exotic material. Lot of blog posts say impossible, expensive, stock pump, etc. Could this be the underlying technology breakthrough? Along with avoiding complex self-assembly in space through decentralization (1 million AI constellation, laser-grid comms).

                [1] https://www.graphene-info.com/smartir-s-graphene-based-radia...

                • This coating looks like it can selectively make parts of the satellite radiators or insulators, as to regulate temperature. But I don't think it can change the fundamental physics of radiating unwanted heat and that you can't do better than black body radiation.
                  • Indeed, graphene seems capable of .99 of black body radiation limit.

                    Quote: "emissivity higher than 0.99 over a wide range of wavelengths". Article title "Perfect blackbody radiation from a graphene nanostructure" [1]. So several rolls of 10 x 50 meters graphene-coated aluminium foil could have significant cooling capability. No science-fiction needed anymore (see the 4km x 4km NVIDIA fantasy)

                    [1] https://opg.optica.org/oe/fulltext.cfm?uri=oe-21-25-30964

                    • What radiators look like is foil or sheet covering fluid loops to spread the heat, control the color, and add surface area.

                      They are usually white, because things in a spacecraft are not hot enough to glow in visible light and you'd rather they not get super hot if the sun shines on them.

                      The practical emittance of both black paint and white paint are very close to the same at any reasonable temperature-- and both are quite good, >90% of this magical material that you cite ;)

                      Better materials -- with less visible absorption and more infrared emittance -- can make a difference, but you still need to convect or conduct the heat to them, and heat doesn't move very well in thin materials as my sibling comment says.

                      The graphene radiator you cite is more about active thermal control than being super black. Cheap ways to change how much heat you are dumping are very useful for space missions that use variable amounts of power or have very long eclipse periods, or what move from geospace to deep space, etc. Usually you solve it on bigger satellites with louvers that change what color they're exposing to the outside, but those are mechanical parts and annoying.

                    • Aluminum foil of great surface will not work very well, because the limited conductivity of a thin foil will create a great temperature gradient through it.

                      Thus the extremities of the foil, which are far from the satellite body, will be much cooler than the body, so they will have negligible contribution to the radiated power.

                      The ideal heatsink has fins that are thick close to the body and they become thinner towards extremities, but a heatsink made for radiation instead of convection needs a different shape, to avoid a part of it shadowing other parts.

                      I do not believe that you can make an efficient radiation heatsink with metallic foil. You can increase the radiating surface by not having a flat surface, but one covered with long fins or cones or pyramids, but the more the surface is increased, the greater the thermal resistance between base and tip becomes, and also the tips limit the solid angle through which the bases radiate, so there must be some optimum shape that has only a limited surface increasing factor over the radiation of a flat body.

                      • > I do not believe that you can make an efficient radiation heatsink with metallic foil.

                        What radiators look like is foil or sheet covering fluid loops to spread the heat, control the color, and add surface area.

                        In general, radiators are white because there's no reason for them to absorb visible light, and they're not hot enough to radiate visible light. You want them to be reflective in the visible spectrum (and strongly absorptive/emissive in the infrared).

                        A white surface pointing at the sun can be quite cool in LEO, < -40C.

                    • It's not as exciting as you think it is. "emissivity higher than 0.99 over a wide range of wavelengths" is basically code for "it's, like, super black"

                      The limiting factor isn't the emissivity, it's that you're having to rely on radiation as your only cooling mechanism. It's super slow and inefficient and it limits how much heat you can dissipate.

                      Like the other person said, you can't do any better than blackbody radiation (emissivity=1).

                      • Lets assume an electrical consumption of 1 MW which turned into heat and a concommitant 3 MW which was a byproduct of acquiring 1 MW of electrical energy.

                        So the total heat load if 4 MW (of which 1 MW was temporarily electrical energy before it was used by the datacenter or whatever).

                        Let's assume a single planar radiator, with emissivity ~1 over the thermal infrared range.

                        Let's assume the target temperature of the radiator is 300 K (~27 deg C).

                        What size radiator did you need?

                        4 MW / (5.67 * 10 ^ -8 W / ( m ^2 K ^4 ) * 300 K ^4) = 8710 m ^2 = (94 m) ^2

                        so basically 100m x 100m. Thats not insanely large.

                        The solar panels would have to be about 3000 m ^2 = 55m x 55m

                        The radiator could be aluminum foil, and something amounting to a remote controlled toy car could drive around with a small roll of aluminum wire and locally weld shut small holes due to micrometeorites. the wheels are rubberized but have a magnetic rim, on the outside theres complementary steel spheres so the radiator foil is sandwiched between wheel and steel sphere. Then the wheels have traction. The radiator could easily weigh less than the solar panels, and expand to much larger areas. Better divide the entire radiator up into a few inflatable surfaces, so that you can activate a spare while a sever leak is being solved.

                        It may be more elegant to have rovers on both inside and outside of the radiator: the inner one can drop a heat resistant silicone rubber disc / sheet over the hole, while the outside rover could do the welding of the hole without obstruction of the hole by a stopgap measure.

                        • > The radiator could be aluminum foil,

                          As I've pointed it out to you elsewhere -- how do you couple the 4MW of heat to the aluminum foil? You need to spread the power somewhat evenly over this massive surface area.

                          Low pressure gas doesn't convect heat well and heat doesn't conduct down the foil well.

                          It's just like how on Earth we can't cool datacenters by hoping that free convection will transfer heat to the outer walls.

                          • Lets assume you truly believe the difficulty is the heat transport, then you correct me, but I never see you correct people who believe the thermal radiation step is the issue. It's a very selective form of correcting.

                            Lets assume you truly believe the difficulty is the heat transport to the radiator, how is it solved on earth?

                            • > Lets assume you truly believe the difficulty is the heat transport, then you correct me, but I never see you correct people who believe the thermal radiation step is the issue

                              It's both. You have to spread a lot of heat very evenly over a very large surface area. This makes a big, high-mass structure.

                              > how is it solved on earth?

                              We pump fluids (including air) around to move large amounts of heat both on Earth and in space. The problem is, in space, you need to pump them much further and cover larger areas, because they only way the heat leaves the system is radiation. As a result, you end up proposing a system that is larger than the cooling tower for many nuclear power plants on Earth to move 1/5th of the energy.

                              The problem is, pumping fluids in space around has 3 ways it sucks compared to Earth:

                              1. Managing fluids in space is a pain.

                              2. We have to pump fluids much longer distances to cover the large area of radiators. So the systems tend to get orders of magnitude physically larger.

                              3. The mass of fluids and all their hardware matters more in space. Even if launch gets cheaper, this will still be true compared to Earth.

                              I explained this all to you 15 hours ago:

                              > If this wasn't a concern, you could fly a big inflated-and-then-rigidized structure and getting lots of area wouldn't be scary. But since you need to think about circulating fluids and actively conducting heat this is much less pleasant.

                              You may notice that the areas, etc, we come up with here to reject 70kW are similar to those of the ISS's EATCS, which rejects 70kW using white-colored radiators and ammonia loops. Despite the use of a lot of exotic and expensive techniques to reduce mass, the radiators mass about 10 tonnes-- and this doesn't count all the hardware to drive heat to them on the other end.

                      • Yes, graphene appears to offer a negligible improvement over other kinds of paints based on black carbon, e.g. Vantablack.

                        The research article linked above does not claim a better emissivity than Vantablack, but a resistance to higher temperatures, which is useful for high temperature sensors (used with pyrometers), but irrelevant for a satellite that will never be hotter than 100 Celsius degrees, in order to not damage the electronic equipment.

              • Entirely depends on band, at 10GHz more like 40%, at lower frequencies more, for example FM band can even go to 70%
            • the majority is likely in radio waves and the inter satellite laser communication
              • Inter sat comms cancels out - every kw sent by one sat is received by another.
                • It doesn't, because the beams are not so tight that they all fall on the target satellite, and not all of that is absorbed :P
            • The radio receiver and transmitter are additional hardware and energy consumption. They add to the heat, not subtract from it.
              • I think you missed the point. If you have a 100 MW communicstion satellite and a 100 MW compute satellite those are very different beasts. The first might send 50% of the energy away as radio communication making it effectively a 50 MW satellitefor cooling purposes.
                • No, they didn't. You can't "send away" thermal energy via radio waves. At the temperatures we're talking about, thermal energy is in the infrared. That's blackbody radiation.
                  • You missed the point.

                    Nobody describes a satellite by specifying the amount of heat that it produces, but by the amount of electrical energy that it consumes.

                    In a communication satellite, a large fraction of the consumed electrical energy goes into the radio transmitter. Radio transmitters are very efficient and most of the consumed power is emitted as radio waves and only a very small part is converted into heat, which must be handled by the cooling system.

                    So in any communication satellite, a significant fraction of the consumed energy does not become heat.

                  • Your answer makes it seem like you too missed the point. If a Starlink sends a 1000W signal to Earth, that is 1000W of power that does not heat the satellite.
          • For another reference, the Nvidia-OpenAI deal is reportedly 10GW worth of DC.
        • It's like this. Everything about operating a datacenter in space is more difficult than it is to operate one on earth.

          1. The capital costs are higher, you have to expend tons of energy to put it into orbit

          2. The maintenance costs are higher because the lifetime of satellites is pretty low

          3. Refurbishment is next to impossible

          4. Networking is harder, either you are ok with a relatively small datacenter or you have to deal with radio or laser links between satellites

          For starlink this isn't as important. Starlink provides something that can't really be provided any other way, but even so just the US uses 176 terawatt-hours of power for data centers so starlink is 1/400th of that assuming your estimate is accurate (and I'm not sure it is, does it account for the night cycle?)

          • What about sourcing and the cost of energy? Solar Panels more efficient, no bad weather, and 100% in sunlight (depending on orbit) in space. Not that it makes up for the items you listed, but it may not be true that everything is more difficult in space.
            • Let's say with no atmosphere and no night cycle, a space solar panel is 5x better. Deploying 5x as many solar panels on the ground is still going to come in way under the budget of the space equivalent.
              • And it's not the same at all. 5x the solar panels on the ground means 5x the power output in the day, still 0 at night. So you'd need batteries. If you add in bad weather and winter, you may need battery capacity for days, weeks or even months, shifting the cost to batteries while still relying on nuclear of fossil backups in case your battery dies or some 3/4/5-sigma weather event outside what you designed for occurs.
                • Or you put the data centers at different points on earth?

                  Or you float them on the ocean circumnavigating the earth?

                  Or we put the datacenters on giant Zeppelins orbiting above the clouds?

                  If we are doing fantasy tech solutions to space problems, why not for a million other more sensible options?

                  • > Or you put the data centers at different points on earth? > Or you float them on the ocean circumnavigating the earth?

                    What that does have to do with anything? If you want to solar-power them, you still are subject to terrestrial effects. You can't just shut off a data center at night.

                    > Or we put the datacenters on giant Zeppelins orbiting above the clouds?

                    They'd have to fly at 50,000+ ft to be clear of clouds, I doubt you can lift heavy payloads this high using bouyancy given the low air density. High risk to people on the ground in case of failure because no re-entry.

                    > If we are doing fantasy tech solutions to space problems, why not for a million other more sensible options?

                    How is this a fantasy? With Starlink operational, this hardly seems a mere 'fantasy'.

                    • > You can't just shut off a data center at night.

                      Why not?

                      A capacity problem can be solved by having another data center the other side of the earth.

                      If it's that the power cycling causes equipment to fail earlier, then that can be addressed far more easily than radiation hardening all equipment so that it can function in space.

                      • Because GPUs are expensive, much more expensive than launch costs if they get starship to the low end of the range they’re aiming for, and you want your expensive equipment running as much as possible to amortize the cost down?
              • That's with current launch costs, right? Nobody is claiming it's economic without another huge fall in launch costs, but that's what SpaceX is doing.
                • It wouldn't make sense if launch was free and it will never be
            • just take cost of getting kg in space and compare it to how much solar panel will generate

              Current satellites get around 150W/kg from solar panels. Cost of launching 1kg to space is ~$2000. So we're at $13.3(3)/Watt. We need to double it because same amount need to be dissipated so let's round it to $27

              One NVidia GB200 rack is ~120kW. To just power it, you need to send $3 240 000 worth of payload into space. Then you need to send additional $3 106 000 (rack of them is 1553kg) worth of servers. Plus some extra for piping

              • Over 10 years ago, the best satellites had 500W/kg [2]. Modern solar panels that are designed to be light are at 200g per sqm [1]. That's 5sqm per kg. One sqm generates ca. 500W. So we're at 2.5kW per kg. Some people claim 4.3kW/kg possible.

                Starship launch costs have a $100/kg goal, so we'd be at $40 / kW, or $4800 for a 120kW cluster.

                120kW is 1GWh annually, costs you around $130k in Europe per year to operate. ROI 14 days. Even if launch costs aren't that low in the beginning and there's a lot more stuff to send up, your ROI might be a year or so, which is still good.

                [1] - https://www.polytechnique-insights.com/en/columns/space/ultr... [2] - https://space.stackexchange.com/questions/12824/lightest-pos...

                • What if you treat that launch costs goal as just a marketing promise. Invest in reality, not in billionaire's fantasies.
                  • > What if you treat that launch costs goal as just a marketing promise.

                    Then it's roughly 10x-15x and still works.

                    > Invest in reality, not in billionaire's fantasies.

                    SpaceX has dramatically reduced payload cost already. How is that a fantasy?

            • I'm stretched to think of one thing that is easier in space. Anything I could imagine still requires getting there (in one piece)
            • Solar panels in space are more efficient, but on the ground we have dead dinosaurs we can burn. The efficiency gain is also more than offset by the fact that you can't replace a worn out panel. A few years into the life of your satellite its power production drops.
              • No idea how quickly they wear out in space with 24x7 irradiance and space temps, but on the earth, they’re at something like 80% capacity after 25 years. So seems like you could control how long they have via overpanelling?
              • If they plan to put this things in a low orbit their useful life before reentry is low anyway.

                A quick search gave me a lifespan of around 5 years for a starlink satellite.

                If you put in orbit a steady stream of new satellites every year maintenance is not an issue, you just stop using worn out or broken ones.

                • Terrestrial data centers save money and recoup costs by salvaging and recycling components, so what you're saying here is that space-based datacenters are even less competitive than we previously estimated.
              • > Solar panels in space are more efficient...

                ... if you completely ignore the difficulty of getting them up there. I'd be interested to see a comparison between the amount of energy required to get a solar panel into space, and the amount of energy it produces during its lifetime there. I wouldn't be surprised if it were a net negative; getting mass into orbit requires a tremendous amount of energy, and putting it there with a rocket is not an efficient process.

                • My sketchy napkin math gives an order of magnitude of a few months of panel output to get it in space.

                  5kg, 500W panel (don’t exactly know what the ratio is for a panel plus protection and frame for space, might be a few times better than this)

                  Say it produces about 350kWh per month before losses.

                  Mass to LEO is something like 10x the weight in fuel alone, so that’s going to be maybe 500kWh. Plus cryogenics etc.

                  So not actually that bad

          • The cost might be the draw (if there is one). Big tech isn't afraid of throwing money at problems, but the AI folk and financiers are afraid of waiting and uncertainty. A satellite is crazy expensive but throwing more money at it gets you more satellites.

            At the end of the day I don't really care either way. It ain't my money, and their money isn't going to get back into the economy by sitting in a brokerage portfolio. To get them to spend money this is as good a way as any other, I guess. At least it helps fund a little spaceflight and satellite R&D on the way.

          • >1. The capital costs are higher, you have to expend tons of energy to put it into orbit

            putting 1KW of solar on land - $2K, putting it into orbit on Starship (current ground-based heavy solar panels, 40kg for 4m2 of 1KW in space) - anywhere between $400 and $4K. Add to that that the costs on Earth will only be growing, while costs in space will be falling.

            Ultimately Starship's costs will come down to the bare cost of fuel + oxidizer, 20kg per 1kg in LEO, i.e. less than $10. And if they manage streamlined operations and high reuse. Yet even with $100/kg, it is still better in space than on the ground.

            And for cooling that people so complain about without running it in calculator - https://news.ycombinator.com/item?id=46878961

            >2. The maintenance costs are higher because the lifetime of satellites is pretty low

            it will live those 3-5 years of the GPU lifecycle.

            • Current cost to LEO is $1500 per kg

              That would make your solar panel (40kg) around $60K to put into space.

              Even being generous and assuming you could get it to $100 per kg that's still $4000

              There's a lot of land in the middle of nowhere that is going to be cheaper than sending shit to space.

              • I think the disconnect is that with starship they’re targeting >200 tons/200,000 kg and $2m-$10m/launch, so the very optimistic case is more like $10/kg. Also, the production of a panel in sun sync orbit is many times one on the ground, doesn’t suffer seasonality/weather, and doesn’t require battery storage for smoothing/time shifting, so you’d need to deploy many times the number of panels on earth. Our home array in North America over the course of the year generates something like 1/7th of its theoretical capacity, overproduces in the summer, and underproduces in the winter.
              • >That would make your solar panel (40kg) around $60K to put into space.

                with the GPU costing the same, it would only double the capex.

                >Even being generous and assuming you could get it to $100 per kg that's still $4000

                noise compare to the main cost - GPUs.

                >There's a lot of land in the middle of nowhere that is going to be cheaper than sending shit to space.

                Cheapness of location of your major investment - GPUs - may as well happen to be secondary to other considerations - power/cooling capacity stable availability, jurisdiction, etc.

                • > with the GPU costing the same, it would only double the capex.

                  Yes, only doubling the capex. With the benefits of, hmm, no maintenance access and awful networking?

                • Any idea, what is the estimated cost of a Google TPU. It may not make sense for Nvidia retail price but at cost price of Google.
                  • Can only speculate out of thin air - B200 and Ryzen 9950x made on the same process and have 11x difference in die size. 11 Ryzens would cost $6K, and with 200Gb RAM - $8K. Googling brings that the B200 cost or production is $6400. That matches the numbers from the Ryzen based estimate above (Ryzen numbers is retail, yet it has higher yield, so balance). So, i'd guess that given Google scale a TPU similar to B200 should be $6K-$10K.
                • > jurisdiction

                  This is the big thing, but Elon's child porn generator in orbit will be subject to US jurisdiction, just as much as if they were in Alaska. I guess he can avoid state law.

                  If jurisdiction is key, you can float a DC in international waters on a barge flying the flag of Panama or similar flag of convenience which you can pretty much buy at this scale. Pick a tin-pot country, fling a few million to the dictator, and you're set - with far less jurisdiction problems than a US, Russia, France launched satellite.

            • > putting 1KW of solar on land - $2K, putting it into orbit on Starship (current ground-based heavy solar panels, 40kg for 4m2 of 1KW in space) - anywhere between $400 and $4K.

              What starship? The fantasy rocket Musk has been promising for 10 years or the real one that has thus far delivered only one banana worth of payload into orbit?

              • it is obviously predicated on Starship. All these discussions have no sense otherwise.

                > or the real one that has thus far delivered only one banana worth of payload into orbit?

                once it starts delivering real payloads, the time for discussions will be no more, it will be time to rush to book your payload slot.

                • You are presented with a factual, verifiable, statement that starship has been promised for years and that all that's been delivered is something capable of sending a banana to LEO. Wayyyy overdue too.

                  You meet this with "well, once it works, it'll be amazing and you'll be queuing up"? How very very musky!

                  What a cult.

                  • I have no idea if SpaceX will ever make the upper stage fully reusable. The space shuttle having existed isn't an existence proof, given the cost of repairs needed between missions.

                    However, with Starship SpaceX has both done more and less than putting a banana in orbit. Less, because it's never once been a true orbit; more, because these are learn-by-doing tests, all the reporting seems to be in agreement that it could already deliver useful mass to orbit if they wanted it to.

                    But without actually solving full reusability for the upper stage, this doesn't really have legs. Starship is cheap enough to build they can waste loads of them for this kind of testing, but not cheap enough for plans such as these to make sense if they're disposable.

                  • They also launched dummy satellites from the "pez dispenser", directly simulating the actual mission payload, about 4 months ago.
            • 1 KW of solar panels is 150€ retail right now. You are probably at 80€ or less if you buy a few MW.

              (I'm ignoring installation costs etc. because actually creating the satellites is ignored here, too)

              • installation of large solar plants is largely automated already
            • > will come down to the bare cost of fuel + oxidizer

              And maintenance and replacing parts and managing flights and ... You're trying to yadda-yadda so much opex here!

              • It is SpaceX/Elon who bet billions on that yadda-yadda, not me. I wrote "If" for $10/kg. I'm sure though that they would easily yadda-yadda under sub-$100/kg - which is $15M per flight. And even with those $100/kg the datacenters in space still make sense as comparable to ground based and providing the demand for the huge Starship launch capacity.

                A datacenter costs ~$1000/ft^2. How much equipment per square foot is there? say 100kg (1 ton per rack plus hallway). Which is $1000 to put into orbit on Starship at $100/kg. At sub-$50/kg, you can put into orbit all the equipment plus solar panels and it would still be cheaper than on the ground.

                • It looks like you’re comparing the cost of installing solar panels on the ground with the cost of just transporting them to orbit. You can’t just toss raw solar panels out of a cargo bay.
                  • >You can’t just toss raw solar panels out of a cargo bay.

                    That is exactly what you do - just like with Starlink - toss out the panels with attached GPUs, laser transmitter and small ion drive.

                    • Best estimates based on the publicly available data I can find are that solar panels make up 5-10% of the manufacturing cost of a starlink satellite.

                      There’s so much overhead you’re hand waving away to make your numbers work.

                • > it is SpaceX/Elon

                  The known scammer guy? Like these ideas wouldn't pass the questions at the end of a primary school presentation.

                • 100 x 100 is 10,000.
            • The bean counters at NVidia recently upped the expected lifecycle from 5 years to 6. On paper, you are expected now to get 6 years out of a GPU for datacenter use, not 3-5.
            • My car costs far more per mile than the bare cost of the fuel. Why would starship not have similar costs?
            • To add space solar cell will weigh only 4-12kg as protection requirements are different.
          • > The maintenance costs are higher because the lifetime of satellites is pretty low

            Presumably they're planning on doing in-orbit propellant transfer to reboost the satellites so that they don't have to let their GPUs crash into the ocean...

            • Another significant factor is that radiation makes things worse.

              Ionizing radiation disrupts the crystalline structure of the semiconductor and makes performance worse over time.

              High energy protons randomly flip bits, can cause latchup, single event gate rupture, destroy hardware immediately, etc.

              • If anything, considering this + limited satellite lifetime, it almost looks like a ploy to deal with the current issue of warehouses full of GPUs and the questions about overbuild with just the currently actively installed GPUs (which is a fraction of the total that Nvidia has promised to deliver within a year or two).

                Just shoot it into space where it's all inaccessible and will burn out within 5 years, forcing a continuous replacement scheme and steady contracts with Nvidia and the like to deliver the next generation at the exact same scale, forever

            • > Presumably they're planning on doing in-orbit propellant transfer to reboost the satellites so that they don't have to let their GPUs crash into the ocean

              Hell, you're going to lose some fraction of chips to entropy every year. What if you could process those into reaction mass?

              • I believe that a modern GPU will burn out immediately. Chips for space are using ancient process nodes with chunky sized components so that they are more resilient to radiation. Deploying a 3nm process into space seems unlikely to work unless you surround it with a foot of lead.
                • Or cooling water/oil?
                  • > Or cooling water/oil?

                    Oh. You surround it with propellant. In a propellant depot.

              • This brings a whole new dimension to that joke about how our software used to leak memory, then file descriptors, then ec2 instances, and soon we'll be leaking entire data centers. So essentially you're saying - let's convert this into a feature.
                • It's certainly one way to do arena-based garbage collection.
              • Reminds me of the proposal to deorbit end of life satellites by puncturing their lithium batteries :)

                The physics of consuming bits of old chip in an inefficient plasma thruster probably work, as do the crawling robots and crushers needed for orbital disassembly, but we're a few years away yet. And whilst on orbit chip replacement is much more mass efficient than replacing the whole spacecraft, radiators and all, it's also a nontrivial undertaking

            • And just like that you've added another not never done before, and definitely not at scale problem to the mix.

              These are all things which add weight, complexity and cost.

              Propellant transfer to an orbital Starship hasn't even been done yet and that's completely vital to it's intended missions.

            • Or maybe they want to just use them hard and deorbit them after three yesrs?
            • "Planning" is a strong word..
          • > Everything about operating a datacenter in space is more difficult than it is to operate one on earth

            Minus one big one: permitting. Every datacentre I know going up right now is spending 90% of their bullshit budget on battlig state and local governments.

            • But since building a datacenter almost anywhere on the planet is more convenient than outer space, surely you can find some suitable location/government. Or put it on a boat, which is still 100 times more sensible than outer space.
              • > since building a datacenter almost anywhere on the planet is more convenient than outer space, surely you can find some suitable location/government

                More convenient. But I'm balancing the cost equation. There are regimes where this balances. I don't think we're there yet. But it's irrational to reject it completely.

                > Or put it on a boat, which is still 100 times more sensible than outer space

                More corrosion. And still, interconnects.

                • > More corrosion

                  Surely given starlinks 5ish year deorbit plan, you could design a platform to hold up for that long... And instead of burning the whole thing up you could just refurbish it when you swap out the actual rack contents, considering that those probably have an even shorter edge lifespan.

                  • Starlinks are built to safely burn up on re-entry. A big reusable platform will have to work quite differently to never uncontrollably re-enter, or it might kill someone by high velocity debris on impact.

                    This adds weight and complexity and likely also forces a much higher orbit.

                    • Hopefully a sea platform does not end up flying into space all of its own, only to crash and burn back down.

                      Maybe the AI workloads running on it achieve escape velocity? ;)

                    • I can’t wait for all the heavy metals that are put into GPUs and other electronics showering down on us constantly. Wonder why the billionaires have their bunkers.
                      • Yeah, "burn up safely on reentry".

                        100 years later: "why does everything taste like cadmium?"

            • If you think there is no papework necessary for launching satellites, you are very very wrong.
              • > If you think there is no papework necessary for launching satellites, you are very very wrong

                I would be. And granted, I know a lot more about launching satellites than building anything. But it would take me longer to get a satellite in the air than the weeks it will take me to fix a broken shelf in my kitchen. And hyperscalers are connecting in months, not weeks.

              • o333
                [flagged]
                • > when he talks about subject outside of his domain

                  Hate to burst your bubble. But I have a background in aerospace engineering. I’ve financed stuff in this field, from launch vehicles to satellites. And I own stakes in a decent chunk of the plays in this field. Both for and against this hypothesis.

                  So yeah, I’ll hold my ground on having reasonable basis for being sceptical of blanket dismissals of this idea as much as I dismiss certainty in its success.

                  There are a lot of cheap shots around AI and aerospace. Some are coming from Musk. A lot are coming from one-liner pros. HN is pretty good at filtering those to get the good stuff, which is anyone doing real math.

                  • That actually confirms what the other commenter said.

                    Your assertion was "Every datacentre I know going up right now is spending 90% of their bullshit budget on battlig state and local governments" and you haven't demonstrated any expertise is building data centers.

                    You've given a very extraordinary claim about DC costs, with no evidence presented, nor expertise cited to sway our priors.

                    • > Your assertion was "Every datacentre I know going up right now is spending 90% of their bullshit budget on battlig state and local governments" and you haven't demonstrated any expertise is building data centers

                      I confirmed "I’ve financed stuff in this field, from launch vehicles to satellites. And I own stakes in a decent chunk of the plays in this field."

                      We're pseudonymous. But I've put more of my personal money to work around hyperscalers, by a mean multiplier of 10 ^ 9, over the troll who's a walking Gell-Mann syndrome.

                      I'm engaging because I want to challenge my views. Reddit-style hot takes are not that.

                  • [flagged]
            • It's also infinitly easier to get 24/7 unadulterated sunlight for your solar panels.
              • Not 24/7 in low earth orbit, but perhaps at an earth-moon or earth-sun L4/L5 lagrange point. Though with higher latency to earth.
              • So what? Why is it important to have 24/7 solar, that you cannot have on the ground? On the ground level you have fossil fuels.

                I wonder if you were thinking about muh emissions for a chemical rocket launched piece of machinery containing many toxic metals to be burnt up in the air in 3-5 years... It doesn't sound more environmentally friendly.

                • Getting enough energy for your AI data centers is one of the most limiting factors for AI technology.

                  Solar in space is about 5-10x as effective as solar on the ground.

                  • So what? Just build some nuclear power plants if AI data centers are so important. It can even work at night when it is infinitely as effective as solar on the ground!

                    Also I'm astounded how important AI data centers are when we are running out of freshwater, to mention a thing we could easily solve with focusing our efforts on it instead of this. But yeah, surely the Space AI Data Centers (aka. "SkyNet") is the most important we must build...

                    Also this is just about Elon jumping the shark...

            • I mean, you don't have zoning in space, but you have things like international agreements to avoid, you know, catastrophic human development situations like kessler syndrome.

              All satellites launched into orbit these days are required to have de-orbiting capabilities to "clean up" after EOL.

              I dunno, two years ago I would have said municipal zoning probably ain't as hard to ignore as international treaties, but who the hell knows these days.

              • > you have things like international agreements to avoid, you know, catastrophic human development

                Yes. These are permitted in weeks for small groups, days for large ones. (In America.)

                Permitting is a legitimate variable that weighs in favor of in-space data centers.

            • > is spending 90% of their bullshit budget on battlig state and local governments

              Source? I can't immediately find anything like that.

              • Parent just means "a lot" and is using 90% to convey their opinion. The actual numbers are closer to 0.083%[1][2][3][4] and parent thinks they should be 0.01-0.1% of the total build cost.

                1. Assuming 500,000 USD in permitting costs. See 2.

                2. Permits and approvals: Building permits, environmental assessments, and utility connection fees add extra expenses. In some jurisdictions, the approval process alone costs hundreds of thousands of dollars. https://www.truelook.com/blog/data-center-construction-costs

                3. Assuming a 60MW facility at $10M/MW. See 4.

                4. As a general rule, it costs between $600 to $1,100 per gross square foot or $7 million to $12 million per megawatt of commissioned IT load to build a data center. Therefore, if a 700,000-square foot, 60-megawatt data center were to be built in Northern Virginia, the world’s largest data center market, it would cost between $420 million and $770 million to construct the facility, including its powered shell and equipping the building with the appropriate electrical systems and HVAC components. https://dgtlinfra.com/how-much-does-it-cost-to-build-a-data-...

                • Yeah, I was trying to be nicer than "you're making it up" just in case someone has the actual numbers.
                • He said bullshit budget, not budget. He's thinking about opportunity and attention costs, not saying that permits literally have a higher price tag than GPUs.
                  • Maybe try meditation? It can help deal with negative emotions.
              • > Source? I can't immediately find anything like that

                I’ve financed two data centers. Most of my time was spent over permitting. If I tracked it minute by minute, it may be 70 to 95%. But broadly speaking, if I had to be told about it before it was solved, it was (a) a real nuisance and (b) not technical.

                • Unless you're the single largest cost, your personal time says nothing about actual DC costs, does it?

                  Just admit it was hyperbole.

            • What counts towards a bullshit budget? Permitting is a drop in the bucket compared to construction costs.
            • that may have been the case before but it is not anymore. I live in Northern VA, the capital of the data centers and it is easier to build one permit-wise than a tree house. also see provisions in OBBB
            • This is a huge one. What Musk is looking for is freedom from land acquisition. Everything else is an engineering and physics problem that he will somehow solve. The land acquisition problem is out of his hands and he doesn't want to deal with politicians. He learned from building out the Memphis DC.
              • Maybe, but I'm skeptical, because current DCs are not designed to minimize footprint. Has anyone even built a two-story DC? Obviously cooling is always an issue, but not, directly, land.

                Now that I think of it, a big hydro dam would be perfect: power and cooling in one place.

                • > Has anyone even built a two-story DC?

                  Downtown Los Angeles: The One Wilshire building, which is the worlds most connected building. There are over twenty floors of data centers. I used Corporate Colo which was a block or two away. That building had at least 10 floors of Data Centers.

                • Multistory DCs are commonplace in major cities.
                • > Has anyone even built a two-story DC?

                  Every DC I’ve been in (probably around 20 in total) has been multi storey.

                • Skepticism is valid. The environmentalists came after dams too.
              • So freedom from law and regulation?
                • [flagged]
                  • Where a random malicious president can't just hijack the government and giga-companies can't trivially lobby lawmakers for profits at the expense of citizens?
                    • A random malicious president ? Who was democractically voted by more than 70% of the country ?
                  • So why does he not build here in Europe then? Getting a permit for building a data center in Sweden is just normal industrial zoning that anyone can get for cheap, there is plenty of it. Only challenge is getting enough electricity.
                    • I meant Europe is an example of how not to do regulation. The problem you just mentioned. If you get land easily electricity won't be available and vice versa.
                      • Then maybe you should move here. We have in most cases well functioning regulations. Of course there are counter examples where it has been bad but data centers is not one of them. It is easy to get permits to build one.
                      • Why is it an example? Can you cite any case where "regulation" trumpled the construction of a properly designed datacenter?

                        Or what you meant was "those poor billionaires can't do as they please with common resources of us all, and without any accountability"?

                        As a quick anecdote, there is a DC in construction in Portugal with a projected capacity of 1.2GW, powered by renewables.

                        • There's also a bunch of countries pretty much begging companies to come and build solar arrays. If you rocked up in Australia and said "I'm building a zero-emission data center we'll power from PV" we'd pretty much fall over ourselves to let you do it. Plus you know, we have just a bonkers amount of land.

                          There is already a Tesla grid levelling battery in South Australia. If what you're really worried about is regulations making putting in the renewable energu expensive, then boy have I got a geopolitically stable, tectonically stable, first-world country where you can do it.

                  • > Not all law and regulation is created equal. Look at Europe.

                    You're spot on but you are not saying what you think you're saying)

              • He "learned" by illegally poisoning black people

                > an engineering and physics problem that he will somehow solve

                no he won't

        • > A Starlink satellite uses about 5K Watts of solar power. It needs to dissipate around that amount (+ the sun power on it) just to operate.

          The “+ solar power” part is the majority of the energy. Solar panel efficiency is only about 25-30% at beginning-of-life whereas typical albedos are effectively 100%. So your estimate is off by at least a factor of three.

          Also, I’m not sure where you got 5 kw from. The area of the satellite is ~100 m2, which means they are intercepting over 100 kw of bolometric solar power.

        • Amazon’s new campus in Indiana is expected to use 2.2GW when complete. 50Mw is nothing, and that’s ignoring the fact that most of that power wouldn't actually be used for compute.
        • Starlink provides a service that couldn't exist without the satellite infrastructure.

          Datacenters already exist. Putting datacenters in space does not offer any new capabilities.

          • This is the main point I think. I am very much convinced that SpaceX is capbable to put a datacenter into space. I am not convinced they can do it cheaper than building a datacenter on earth.
            • I would be a lot more convinced they had found a way to solve the unit economics if it was being used to secure billion dollar deposits from other companies rather than as the narrative for rolling a couple of Elon's loss making companies into SpaceX and IPOing...
        • > Isn't 50MW already by itself equivalent to the energy consumption of a typical hyperscaler cloud?

          xAI’s first data center buildout was in the 300MW range and their second is in the Gigawatt range. There are planned buildouts from other companies even bigger than that.

          So data center buildouts in the AI era need 1-2 orders of magnitude more power and cooling than your 50MW estimate.

          Even a single NVL72 rack, just one rack, needs 120kW.

        • 5kW means you can't even handle a single one of these[0], compared to a handful per rack on an earthbound data centre.

          0. https://www.arccompute.io/solutions/hardware/gpu-servers/sup...

        • I ran the math the last time this topic camps up

          The short answer is that ~100m2 of steel plate at 1400C (just below its melting point) will shed 50MW of power in black body radiation.

          https://news.ycombinator.com/item?id=46087616#46093316

          • The temperature of space datacenters will be limited to 100 Celsius degrees, because otherwise the electronic equipment will be destroyed.

            So your huge metal plate would radiate (1673/374)^4 = 400 times less heat, i.e. only 125 kW.

            In reality, it would radiate much less than that, even if made of copper or silver covered with Vantablack, because the limited thermal conductivity will reduce the temperature for the parts distant from the body.

          • Which GPU runs at 1400C?
            • One made of steel presumably.

              I would assume such a setup involves multiple stages of heat pumps to from GPU to 1400C radiatoe. Obviously that's going to impact efficiency.

              Also I'm not seriously suggesting that 1400C radiators is a reasonable approach to cooling a space data centre. It's just intended to demonstrate how infeasible the idea is.

              • The idea of using heat pumps to increase the temperature of the radiator is unlikely to allow an increase of the fraction of the original amount of heat that is radiated per heatsink surface, i.e. the added heat may be higher than the additionally radiated heat, though I am too lazy to compute now whether this is possible.

                Moreover, a heat pump would add an equipment with moving parts that can fail, requiring maintenance.

        • Starlink satellites also radiate a non-trivial amount of the energy they consume from their phased arrays
        • Not related to heat, but a com satellite is built from extremely durable HW/SW that's been battle-tested to run flawlessly over years with massive MTBF numbers.

          A data center is nowhere near that and requires constant physical interventions. How do they suggest to address this?

        • 50MW is on the small side for an AI cluster - probably less than 50k gpus.

          if the current satellite model dissipates 5kW, you can't just add a GPU (+1kW). maybe removing most of the downlink stuff lets you put in 2 GPUs? so if you had 10k of these, you'd have a pretty high-latency cluster of 20k GPUs.

          I'm not saying I'd turn down free access to it, but it's also very cracked. you know, sort of Howard Hughesy.

          • High latency to earth but low latency (potentially) to other satellites.
        • 50MW might be one aisle of a really dense DC. A single rack might draw 120kW.
        • Are starlink satellites in sun synchronous orbits? Doesn't constant solar heating change the energy balance quite a bit?
        • A Starlink satellite is mainly just receiving and sending data, the bare minimum of a data center-satellite's abilities; everything else comes on top and would be the real power drain.
        • Forget heat. Replacing disks alone is a deal breaker on that one.
        • > A Starlink satellite uses about 5K Watts of solar power. It needs to dissipate around that amount (+ the sun power on it) just to operate.

          This isn't quite true. It's very possible that the majority of that power is going into the antennas/lasers which technically means that the energy is being dissipated, but it never became heat in the first place. Also, 5KW solar power likely only means ~3kw of actual electrical consumption (you will over-provision a bit both for when you're behind the earth and also just for safety margin).

        • > A Starlink satellite uses about 5K Watts of solar power

          Is that 5kW of electrical power input at the terminals, or 5kW irradiation onto the panels?

          Because that sounds like kind of a lot, for something the size of a fridge.

        • Because 10K satellites have a FAR greater combined surface area than a single space-borne DC would. Stefan-Boltzman law: ability to radiate heat increase to the 4th power of surface area.
          • It's linear to surface area, but 4th power to temperature.
            • Also worth noting that if computing power scales with volume then surface area (and thus radiation) scales like p^2/3. In other words, for a fixed geometry, the required heat dissipation per unit area goes like p^1/3. This is why smaller things can just dissipate heat from their surface, whereas larger things require active cooling.

              I'm not a space engineer but I'd imagine that smaller satellites can make due with a lot of passive cooling on the exterior of the housing, whereas a shopping-mall sized computer in space would will require a lot of extra plumbing.

            • Thanks for the correction. Last time I looked at it was in 2nd year Thermodynamics in 1985.
        • Square–cube law.
        • Why would anyone think the unit cost would be competitive with cheap power / land on earth? If that doesn't make sense how could anything else?
        • A typical desktop/tower PC will consume 400 watts. So 12 PC's equals 1 starlink satellite.

          A single server in a data center will consume 5-10 kW.

        • > Why is starlink possible and other computations are not?

          Aside from the point others have made that 50 MW is small in the context of hyperscalers, if you want to do things like SOTA LLM training, you can't feasibly do it with large numbers of small devices.

          Density is key because of latency - you need the nodes to be in close physical proximity to communicate with each other at very high speeds.

          For training an LLM, you're ideally going to want individual satellites with power delivery on the order of at least about 20 MW, and that's just for training previous-generation SOTA models. That's nearly 5,000 times more power than a single current Starlink satellite, and nearly 300 times that of the ISS.

          You'd need radiator areas in the range of tens of thousands of square meters to handle that. Is it theoretically technically possible? Sure. But it's a long-term project, the kind of thing that Musk will say takes "5 years" that will actually take many decades. And making it economically viable is another story - the OP article points out other issues with that, such as handling hardware upgrades. Starlink's current model relies on many cheap satellites - the equation changes when each one is going to be very, very expensive, large, and difficult to deploy.

        • Sure, we can run the math on heat dissipation. The law of Stefan-Boltzman is free and open source and it application is high school level physics. You talk about 50 MW. You are going to need a lot of surface area to radiate that off at somewhere close to reasonable temperatures.
          • > The law of Stefan-Boltzman is free and open source... What do you mean by "open source"? Can we contribute changes to it?
      • > 10th (or worse) best AI company

        You might only care about coding models, but text is dominating the market share right now and Grok is the #2 model for that in arena rankings.

        • Arena rankings, lol.

          Openrouter is a decent proxy for real world use and Grok is currently 8% of the market: https://openrouter.ai/rankings (and is less than 7% of TypeScript programming)

          • 5th place company or better in every chart on that page except 'fastest models' suggests that parent is still right to criticize the 10th place characterization.
            • They sure are right to criticize but not by this specific evidence: "text is dominating the market share right now and Grok is the #2 model for that in arena rankings"
        • Grok is losing pretty spectacularly on the user / subscriber side of things.

          They have no path to paying for their existence unless they drastically increase usage. There aren't going to be very many big winners in this segment and xAI's expenses are really really big.

          • I really wonder what will happen when the AI companies can no longer set fire to piles of investor money, and have to transition to profitability or at least revenue neutrality - as that would entail dramatically increasing prices.

            Is the plan to have everyone so hopelessly dependent on their product that they grit their teeth and keep on paying?

            • The answer to this is very very simple.

              Think about the stock return over a period - its composed of capital gains and dividends.

              Now what happens capital gains disappears and perhaps turns into capital losses? Dividends have to go higher.

              What does this mean? Less retained earnings / cashflows that can be re-invested.

              Apple is the only one that will come out of this OK. The others will be destroyed for if they dont return cash, the cash balance will be discounted leading to a further reduction in the value of equity. The same thing that happened to Zuckerberg and Meta with the Metaverse fiasco.

              Firms in the private sphere will go bust/acquired.

              • > Now what happens capital gains disappears and perhaps turns into capital losses? Dividends have to go higher

                This is not how corporate finance works. Capital gains and losses apply to assets. And only the most disciplined companies boost dividends in the face of decline—most double down and try to spend their way back to greatness.

            • It'll be a combination of advertising and subscription fees, and there will only be a few big winners.

              Gemini is practically guaranteed. With the ad model already primed, their financial resources, their traffic to endlessly promote Gemini (ala Chrome), their R&D capabilities around AI, their own chips, crazy access to training data, and so on - they'd have to pull the ultimate goof to mess up here.

              Microsoft is toast, short of a miracle. I'd bet against Office and Windows here. As Office goes down, it's going to take Windows down with it. The great Office moat is about to end. The company struggles, the stock struggles, Azure gets spun off (unlock value, institutional pressure), Office + Windows get spun off - the company splits into pieces. The LLMs are an inflection point for Office and Microsoft is super at risk, backwards regarding AI and they're slow. The OpenAI pursuit as it was done, was a gigantic mistake for Microsoft - one of the dumbest strategies in the history of tech, it left them with their pants down. Altman may have killed a king by getting him to be complacent.

              Grok is very unlikely to make it (as is). The merger with SpaceX guarantees its death as a competitor to GPT/Gemini/Claude, it's over. Maybe they'll turn Grok into something useful to SpaceX. More likely they'll slip behind and it'll die rapidly like Llama. The merger is because they see the writing on the wall, this is a bailout to the investors (not named Elon) of xAI, as the forced Twitter rollup was a bailout for the investors of Twitter.

              Claude is in a weird spot. What they have is not worth $300-$500 billion. Can they figure out how to build a lot more value out of what they have today (and get their finances sustainable), before the clock runs out? Or do they get purchased by Meta, Microsoft, etc.

              OpenAI has to rapidly roll out the advertising model and get the burn rate down to meaningless levels, so they're no longer dependent on capital markets for financing (that party is going to end suddenly).

              Meta is permanently on the outside looking in. They will never field an in-house competitor to GPT or Gemini that can persistently keep up. Meta doesn't know what it is or why it should be trying to compete with GPT/Gemini/Claude. Their failure (at this) is already guaranteed. They should just acquire GPT 4o and let their aging userbase on FB endlessly talk itself into the grave for the next 30 years while clicking ads.

              If Amazon knew what they were doing (they don't right now), they would: immediately split retail + ads and AWS. The ad business ensures that the retail business will continue to thrive and would be highly lucrative. Then have AWS purchase Anthropic when valuations drop, bolt it on to AWS everything. Far less of an anti-trust issue than if what is presently known as Amazon attempted it here and now. Anthropic needs to build a lot on to itself to sustain itself and justify its valuation, AWS already has the answer to that.

              If valuations plunge, and OpenAI is not yet sustainable, Microsoft should split itself into pieces and have the Windows-Office division purchase OpenAI as their AI option. It'd be their only path to avoiding anti-trust blocking that acquisition. As is Microsoft would not be allowed to buy OpenAI. Alternatively Microsoft can take a shot at acquiring Anthropic at some point - this seems likely given the internal usage going on at Redmond, the primary question is anti-trust (but in this case, Anthropic is viewed as the #3, so Microsoft would argue it bolsters competition with GPT & Gemini).

              • *Altman may have killed a king by getting him to be complacent.*

                I still think a lot about the failed OpenAI coup, and how different things would be now if Microsoft hadn't backed Altman. Would this hype cycle and bubble grown so ridiculous if there were more conscientious people in charge at the front-runner? We will unfortunately never know. I really wish that board had planned out their coup better.

              • Why do you say Amazon doesn't know what they are doing? I think among those mentioned, they are the best positioned alongside Apple in the grander schema of things.

                Also you say meta will never field a competitor to GPT - but they did llama; not as a commercial product, but probably an attempt at it (and failed). Otherwise agreed.

              • "Gemini is practically guaranteed. With the ad model already primed, their financial resources, their traffic to endlessly promote Gemini (ala Chrome), their R&D capabilities around AI, their own chips, crazy access to training data, and so on - they'd have to pull the ultimate goof to mess up here"

                Im not convinced on this TBH in the long-run. Google is seemingly a pure play technology firm that has to make products for the sake of it, else the technology is not accessible/usable. Does that mean they are at their core a product firm? Nah. Thats always been Apple's core thing, along side superior marketing.

                One only has to compare Google's marketing of the Pixel phone to Apple - it does not come close. Nobody connects with Google's ads, the way they do with Apple. Google has a mountain to climb and has to compensate the user tremendously for switching.

                Apple will watch the developments keenly and figure out where they can take advantage of the investments others have made. Hence the partnerships et al with Google.

          • Merging with SpaceX means they don't have to pay for their existence. Anyway they're probably positioned better than any other AI player except maybe Gemini.
            • I don’t follow why merging with SpaceX means they don’t have to pay for their existence. Someone does. Presumably now that is SpaceX. What is SpaceX’s revenue?
              • Maybe the idea is that SpaceX has access to effectively unlimited money through the US Government, either via ongoing lucrative contracts, or likely bailouts if needed. The US Govt wouldn't bail out xAI but they would bail out SpaceX if they are in financial trouble.
                • Bingo! Elon's main life mission now is to roll back social progress via the anti-woke combination of xAI and Twitter. That's why he's tying them to the now rather-essential SpaceX, despite possibly hurting its IPO. He can now keep pumping money into them without a worry.
      • Plus government backstop. The federal government (especially the current one) is not going to let SpaceX fail.
        • Maybe not, but they might force it to sell at fire sale prices to another aerospace company that doesn't have the baggage.
      • xAI includes twitter? I thought twitter was just X?
        • xAI acquired twitter in 2025 as part of Musk's financial shell game (probably the same game he is playing with SpaceX/xAI now).
      • Elon's always looking for another Brooklyn Bridge to sell to the rubes...
      • Sounds like Elon hurt someone’s feelings
    • > Space is a vacuum. i.e. The lack-of-a-thing that makes a thermos great at keeping your drink hot.

      1) The heat can be transported by a heat carrier conducting heat standing still.

      2) The heat can be transported by a heat carrier in motion.

      3) The heat can be transported by thermal radiation.

      The first 2 require massive particles, the latter are spontaneous photons.

      A thermos bottle does not simply work by eliminating the motile mass particles.

      Lets consider room temperature as the outer thermos temperature and boiling hot water as the inner temperature, that is roughly 300 K and 400 K.

      Thermal radiation is proportional to the fourth power of temperature and proportional to emissivity (which is between 0 and 1).

      Lets pretend you are correct and thus thermally blackened glass (emissivity 1) inside the vacuum flask would be fine according to you. That would mean that the radiation from your tea to the room temperature side would be proportional to 400^4 while the thermal radiation from room temperature to the tea would be proportional to 300^4. Since (400/300) ^ 4 = 3.16 that means the heat transport from hot tea to room temperature is about 3 times higher.

      If on the other hand the glass was aluminized before being pulled vacuum the heat transports are proportional to 0 * 400 K ^ 4 and 0 * 300 K ^ 4 . So the heat transport in either direction would be 0 and no net heat transport remains.

      If you believe the shiny inside of your thermos flask is an aesthetic gimmick, think again.

      You are making a non-comparison.

      Imagine comparing a diesel engine car to an electric car, but first removing the electric motor. Does that make a fair comparison???

    • In 2024, Starcloud posted their plans to "solve" the cooling problem. https://starcloudinc.github.io/wp.pdf

      > As conduction and convection to the environment are not available in space, this means the data center will require radiators capable of radiatively dissipating gigawatts of thermal load. To achieve this, Starcloud is developing a lightweight deployable radiator design with a very large area - by far the largest radiators deployed in space - radiating primarily towards deep space...

      They claim they can radiate "633.08 W / m^2". At that rate, they're looking at square kilometers of radiators to dissipate gigawatts of thermal load, perhaps hectares of radiators.

      They also claim that they can "dramatically increase" heat dissipation with heat pumps.

      So, there you have it: "all you have to do" is deploy a few hectares of radiators in space, combined with heat pumps that can dissipate gigawatts of thermal load with no maintenance at all over a lifetime of decades.

      This seems like the sort of "not technically impossible" problem that can attract a large amount of VC funding, as VCs buy lottery tickets that the problem can be solved.

    • It has been worked out. Just look at how big are ISS radiators and that they dissipate around 100kW then calculate cost of sending all that to space. And by that I mean it would be even more expensive that some of the estimates flying around

      While personally I think it's another AI cash grab and he just wants to find some more customers for spacex, other thing is "you can't copyright infringe in space" so it might be perfect place to load that terabytes of stolen copyrighted material to train data sets, if some country suddenly decides corporation stealing copyright content is not okay any more

      • DGX H200 is 10,2 kW. So that like 10 of them. Or only 80 H200. Doesn’t sound like a big data center. More like a server room.

        ISS radiators are huge 13.6x3.1 m. Each radiates 35 kW. So you need 3 of them to have your 100 kW target. They are also filled with gas that needs pumping so not exactly a passive system and as such can break down for a whole lot of reasons.

        You also need to collect that power so you need about the same amount of power coming from solar panels. ISS solar array wings are 35x12 m and can generate about 31 kW of power. So we’ll need at least 3 of them. BTW each weighs a ton, a literal metric ton.

        It hardly seems feasible. Huge infrastructure costs for small AI server rooms in space.

        • if I may add, you can't really launch a station three times the size of ISS with a single rocket so there will be multiple launches. Just the launch costs alone could likely finance multiple similarly sized server rooms on land.
      • Maybe you can't copyright infringe in space, but it's still infringement when the result gets back to earth.
        • These major AI tools have already been trained on infringing works.
        • Keep the result in space, and use large telescopes to look at it!
          • the result is the result. If you look at it and use it for something, you have moved the result. Its not a physical object that exists in a place, its an idea. Hence IP. Intellectual property.
            • Really depends on how good your lawyers are
    • Its very simple, xAI needs money to win the AI race, so best option is to attach to Elon’s moneybank (spacex) to get cash without dilution
      • Remember how he argued for Tesla’s Solarcity acquisition because solar roofs?

        Data centers in space are the same kind of justification imo.

        • Solar roofs are much more practical to be honest.
          • Putting solar roofs on a building? For a car company?
            • There's a synergy effect here - Tesla sells you a solar roof and car bundle, the roof comes without a battery (making it cheaper) and the car now gets a free recharge whenever you're home (making it cheaper in the long term).

              Of course that didn't work out with this specific acquisition, but overall it's at least a somewhat reasonable idea.

            • In comparison to datacenters in space yes. Solar roofs are already a profitable business, just not likely to be high growth. Datacenters in space are unlikely to ever make financial sense, and even if they did, they are very unlikely to show high growth due to continuing ongoing high capital expenses inherent in the model.
              • I think a better critique of space-based data centres is not that they never become high growth, it's just that when they do it implies the economy is radically different from the one we live in to the degree that all our current ideas about wealth and nations and ownership and morality and crime & punishment seem quaint and out-dated.

                The "put 500 to 1000 TW/year of AI satellites into deep space" for example, that's as far ahead of the entire planet Earth today as the entire planet Earth today is from specifically just Europe right after the fall of Rome. Multiplicatively, not additively.

                There's no reason to expect any current business (or nation, or any given asset) to survive that kind of transition intact.

            • It's obviously a pretty weird thing for a car company to do, and is probably just a silly idea in general (it has little obvious benefit over normal solar panels, and is vastly more expensive and messy to install), but in principle it could at least work, FSOV work. The space datacenter thing is a nonsensical fantasy.
            • For an electrification company.
          • [dead]
      • > win the AI race

        I keep seeing that term, but if it does not mean "AI arms race" or "AI surveillance race", what does it mean?

        Those are the only explanations that I have found, and neither is any race that I would like to see anyone win.

        • Big tech businesses are convinced that there must be some profitable business model for AI, and are undeterred by the fact that none has yet been found. They want to be the first to get there, raking in that sweet sweet money (even though there's no evidence yet that there is money to be made here). It's industry-wide FOMO, nothing more.
          • Typically in capitalism, if there is any profit, the race is towards zero profit. The alternative is a race to bankrupt all competitors at enormous cost in order to jack up prices and recoup the losses as a monopoly (or duopoly, or some other stable arrangement). I assume the latter is the goal, but that means burning through like 50%+ of american gdp growth just to be undercut by china.

            Imo I would be extremely angry if I owned any spacex equity. At least nvidia might be selling to china in the short term... what's the upside for spacex?

            • > The alternative is a race to bankrupt all competitors at enormous cost in order to jack up prices and recoup the losses as a monopoly

              I don't know of an instance of this happening successfully.

              • taxi apps, delivery apps, social media apps—all of these require a market that's extremely expensive to build but is also extremely lucrative to exploit and difficult to unseat. You see this same model with big-box stores displacing local stores. The secret to making a lot of money under capitalism is to have a lot of money to begin with.
              • Walmart? It's certainly more successful in physical markets
                • See Amazon
                  • Different markets entirely—I can't walk into amazon, and I don't order online from Walmart.
                  • Are you saying that Amazon is a successful monopoly, or that Amazon is even with massive expenses still not a full monopoly?
              • Amazon
          • People keep saying this but it's simply untrue. AI inference is profitable. Openai and Anthropic have 40-60% gross margins. If they stopped training and building out future capacity they would already be raking in cash.

            They're losing money now because they're making massive bets on future capacity needs. If those bets are wrong, they're going to be in very big trouble when demand levels off lower than expected. But that's not the same as demand being zero.

            • those gross profit margins aren't that useful since training at fixed capacity is continually getting cheaper, so there's a treadmill effect where staying in business requires training new models constantly to not fall behind. If the big companies stop training models, they only have a year before someone else catches up with way less debt and puts them out of business.
              • Only if training new models leads to better models. If the newly trained models are just a bit cheaper but not better most users wont switch. Then the entrenched labs can stop training so much and focus on profitable inference
                • If they really have 40-60% gross margins, as training costs go down, the newly trained models could offer the same product at half the price.
                  • Well thats why the labs are building these app level products like claude code/codex to lock their users in. Most of the money here is in business subscriptions I think, how much savings would be required for businesses to switch to products that arent better, just cheaper?
                    • I think the real lock-in is in "CLAUDE.md" and similar rulesets, which are heavily AI specific.
                • [dead]
            • > Openai and Anthropic have 40-60% gross margins.

              Stop this trope please. We (1) don't really know what their margins are and (2) because of the hard tie-in to GPU costs/maintenance we don't know (yet) what the useful life (and therefore associated OPEX) is of GPUs.

              > If they stopped training and building out future capacity they would already be raking in cash.

              That's like saying "if car companies stopped researching how to make their cars more efficient, safer, more reliable they'd be more profitable"

          • It will be genuinely interesting to see what happens first, the discovery of such a model, or the bubble bursting.
        • A significant number of AI companies and investors are hoping to build a machine god. This is batshit insane, but I suppose it might be possible. Which wouldn't make it any more sane.

          But when they say, "Win the AI race," they mean, "Build the machine god first." Make of this what you will.

          • On the edge of my seat waiting to see what hits us first, a massive economic collapse when the hype runs out, or the Torment Nexus.
            • It really seems like the market has locked in on one of those two things being a guaranteed outcome at this point.
        • It’s a graft to keep people distracted and allow for positioning as we fall off the end of the fossil energy boom.
        • It’s a framing device to justify the money, the idea being the first company (to what?) will own the market.
        • Being too far ahead for competitors to catch up, similar to how google won browsers, amazon won distribution, etc
      • I’m not certain spacex is generating much cash right now ?

        Starship development is consuming billions. F9 & Starlink are probably profitable ?

        I’d say this is more shifting of the future burden of xAI to one of his companies he knows will be a hit stonk when it goes public, where enthusiasm is unlikely to be dampened by another massive cash drain on the books.

      • > xAI needs money to win the AI race

        Off on a tangent here but I'd love for anyone to seriously explain how they believe the "AI race" is economically winnable in any meaningful way.

        Like what is the believed inflection point that changes us from the current situation (where all of the state-of-the-art models are roughly equal if you squint, and the open models are only like one release cycle behind) to one where someone achieves a clear advantage that won't be reproduced by everyone else in the "race" virtually immediately.

        • Like any other mega-scaler, theyre just playing Money Chicken.

          Everyone is spending crazy amounts of money in the hopes that the competition will tap out because they can't afford it anymore.

          Then they can cool down on their spending and increase prices to a sustainable level because they have an effective monopoly.

          • Money Chicken is the best term I've seen for this!
        • I _think_ the idea is that the first one to hit self improving AGI will, in a short period of time, pull _so_ far ahead that competition will quickly die out, no longer having any chance to compete economically.

          At the same time, it'd give the country controlling it so much economic, political and military power that it becomes impossible to challenge.

          I find that all to be a bit of a stretch, but I think that's roughly what people talking about "the AI race" have in mind.

        • > Off on a tangent here but I'd love for anyone to seriously explain how they believe the "AI race" is economically winnable in any meaningful way.

          Because the first company to have a full functioning AGI will most likely be the most valuable in the world. So it is worth all the effort to be the first.

          • > Because the first company to have a full functioning AGI will most likely be the most valuable in the world.

            This may be what they are going for, but there are two effectively religious beliefs with this line of thinking, IMO.

            The first is that LLMs lead to AGI.

            The second is that even if the first did turn out to be true that they wouldn't all stumble into AGI at the same time, which given how relatively lockstep all of the models have been for the past couple of years seems far more likely to me than any single company having a breakthrough the others don't immediately reproduce.

        • They ultimately want to own everyone's business processes, is my guess. You can only jack up the subscription prices on coding models and chatbots by so much, as everyone has already noted... but if OpenAI runs your "smart" CRM and ERP flows, they can really tighten the screws.
          • If you have the greatest coding agent under your thumb, eventually you orient it toward eating everything else instead of letting everybody else use your agent to build software & make money. Go forward ten years, it's highly likely GPT, Gemini, maybe Claude - they'll have consumed a very large amount of the software ecosystem. Why should MS Office exist at all as a separate piece of software? The various pieces of Office will be trivial for the GPT (etc) of ten years out to fully recreate & maintain internally for OpenAI. There's no scenario where they don't do what the platforms always do: eat the ecosystem, anything they can. If a platform can consume a thing that touches it, it will.

            Office? Dead. Box? Dead. DropBox? Dead. And so on. They'll move on anything that touches users (from productivity software to storage). You're not going to pay $20-$30 for GPT and then pay for DropBox too, OpenAI will just do an Amazon Prime maneuver and stack more onto what you get to try to kill everyone else.

            Google of course has a huge lead on this move already with their various prominent apps.

            • Dropbox is actually a great example of why this isn't likely to happen. Deeper pocketed competition with tons of cloud storage and the ability to build easy upload workflows (including directly into software with massive install base) exists, and showed an active interest in competing with them. Still doing OK

              Office's moat is much bigger (and its competition already free). "New vibe coded features every week" isn't an obvious reason for Office users to switch away from the platform their financial models and all their clients rely on to a new upstart software suite

      • That may be the plan, but this is also a great way for GDPR's maximum fine, based on global revenue, to bite on SpaceX's much higher revenue. And without any real room for argument.
    • The energy economics in space are also a bit more complicated than usually thought. I think Starlink has been using Si cells instead of III-V-based ones, but in addition to lower output they also tend to degrade faster under radiation. I guess that's ok if the GPU is going to be toast in a few years anyway so you might as well de-orbit the whole thing. But that same solar cell on Earth will happily be producing for 40+ years.

      Also the same issue with radiative cooling pops up for space solar cells - they tend to run way hotter than on Earth and that lowers their efficiency relative to what you could get terrestrially.

    • People did the calculation: radiative cooling requires smaller surface area than solar panels. So, basically, a solar panel itself can radiate heat.

      Have you done a calculation yourself?

      • How can the solar panel itself radiate heat when it's being heated up generating supplying power? Looking at pictures of the ISS there's radiators that look like they're there specifically to cool the solar panels.

        And even if viable, why would you just not cool using air down on earth? Water is used for cooling because it increases effectiveness significantly, but even a closed loop system with simple dry air heat exchangers is quite a lot more effective than radiative cooling

        • You take the amount of energy absorbed by the solar panels and subtract the amount they radiate. Most things in physics are linear systems that work like this.
      • The same radiative (radiant) cooling on Earth works almost just as well, but without the cost of a rocket launch.
    • (DTC) Datacentres take electricity and turn it into low grade heat e.g 60c water. Put them anywhere where you've either got excess (cheap) energy or where you can use the heat. Either is fine, both is great, but neither is both bad and current standard practice.

      It's perfectly possible to put small data centres in city centres and pipe the heat around town, they take up very very little space and if you're consuming the heat, you don't need the noisy cooling towers (Ok maybe a little in summer).

      Similarly if you stick your datacentre right next to a big nuclear power plant, nobody is even going to notice let alone care.

      • Well a few considerations:

        - You have to size your cooling towers for your hottest hour. Doing this saves you no capital costs.

        - You barely have to run the fans on your cooling towers in the winter because the air is so cold. So often this also won’t save you much operating costs.

        - Already there is an essentially unlimited amount of so called “waste heat” from power plants and factories. Building district heating systems is extremely capital intensive, which is why this isn’t done more.

        - As a municipality it’s just a horrible idea to make the heating system of your whole city rely on a random company continuing to operate (even worse if said company is in a potential bubble). This is why most district heating systems work with power plants - they already have the government involved in ensuring their continuing operations.

        • I don't think I ever said it reduced capital cost. I agree (though you might be willing to take more risk on reducing redundancy e.g instead of 2+1 cooling towers you may be more willing to just buy 2).

          You cannot put a power station in the middle of a city centre, you can put a datacentre there. The main reason this isn't done more is that it's expensive to build heat network between the 'far out of town industrial area' where they put the heat sources and the city centre where the heat consumers are.

          I don't know why a municipality is involved, but regardless you can simply install a backup heat source and/or add a mix of heat suppliers to the network. Backup gas boiler or similar is not that problematic or expensive to add particularly because you don't need to add redundancy as it's just there for a backup scenario.

      • Resistive heating is a tremendously inefficient way to generate heat. Sometimes it's worth it if you get something useful in exchange (such as full spectrum light in the winter). But it's not all upsides.

        Heat pumps are magic. They're something like 300% efficient. Each watt generates 3 watts of useful heat.

        • I share your enthusiasm about heat pumps, but I wonder what the efficiency of using waste heat is. Couldn't it be competitive with heat pumps? As it's a waste product, isn't it reasonable to also expect it to be more than 100% efficient?
          • As a rule of thumb (obviously it varies) you spend about 1% pumping water round a heat network. So your CoP is around 99 if you consider heat truly free. It's actually higher as pump energy largely is converted to friction/heat.
          • You can’t extract energy from heat by itself. Only from a heat delta.

            Think of heat like flowing water or charge. Only an altitude or voltage delta creates the flow needed to harvest energy.

            You get no useful energy from heat you are already trying to shed because you have no delta to work with. (The entire problem exists because there is no surrounding environment with high heat capacity and lower heat.)

            • What is waste heat depends on your usecase. Using waste heat from industrial processes for district heating is done in some places.
              • Yes, because there is a heat delta. A heat difference.

                Using higher heat to raise lower heat is just the most simple case.

                But purpose isn't relevant to this constraint, it is a physics constraint. You can never extract energy from heat without a heat difference to work with. (And without a heat difference, even "heating" with heat doesn't do anything.)

          • Much more than 100% since the only energy you need to put in is for pumping the hot water around.
        • Its not inefficient if you were creating the heat anyway, its a completely free byproduct.
          • Yeah. This. Obviously if the objective is just to generate heat only buy a heat pump and not a B200!
    • > It makes far more sense to build data centers in the arctic.

      What (literally) on earth makes you say this? The arctic has excellent cooling and extremely poor sun exposure. Where would the energy come from?

      A satellite in sun-synchronous orbit would have approximately 3-5X more energy generation than a terrestrial solar panel in the arctic. Additionally anything terrestrial needs maintenance for e.g. clearing dust and snow off of the panels (a major concern in deserts which would otherwise seem to be ideal locations).

      There are so many more considerations that go into terrestrial generation. This is not to deny the criticism of orbital panels, but rather to encourage a real and apolitical engineering discussion.

      • > A satellite in sun-synchronous orbit would have approximately 3-5X more energy generation than a terrestrial solar panel in the arctic.

        Building 3-5x more solar plants in the Arctic, would still be cheaper than travelling to space. And that's ignoring that there are other, more efficient plants possible. Even just building a long powerline around the globe to fetch it from warmer regions would be cheaper.

        • > Even just building a long powerline around the globe to fetch it from warmer regions would be cheaper.

          Deserts have good sun exposure and land availability but extremely poor water resources, which is necessary for washing the sand off the panels. There are many challenges with scaling both terrestrial and orbital solar.

          • I wasn't thinking of going THAT far. Northern Canada/Alaska is in the arctic region, so build the line some thousand miles down to the sunny parts of Canada/USA and call it done. Not like this is particularly hard, probably not even that expensive, compared to a million satellites/future space-debris. Greenland would probably be also a good location.
        • > Building 3-5x more solar plants in the Arctic, would still be cheaper than travelling to space.

          Well first you have to make solar panels works in the polar nights, in winter they have a few minutes of sun in the day at most.

        • Sunlight is unevenly distributed in the arctic during the year to say the least.
    • I think he has rocket company that needs more work.

      Sufficient hype funds more work for his rocket company.

      The more work they have the faster they can develop the systems to get to Mars. His pet project.

      I really think it's that simple.

      • Starlink and Falcon 9 have been an excellent pairing, Falcon 9 partially reusable rockets created a lot launch capacity and starlink filled the demand. Starship if it meets its goals will create more launch fully reusable supply by orders of magnitude, but there is not the demand for all that launch capacity. Starlink can take some of it but probably not all so they need to find a customer to fill it in order to build up enough to have the volume to eventually colonize mars.
        • Going to Mars is not a serious goal.

          We can tell because it’s not being treated as a serious goal. 100% of the focus is on the big vroom vroom part that’s really exciting to kids who get particularly excited by things that go vroom, and approximately 0% of the focus is on developing all the less glamorous but equally essential components of a successful Mars mission, like making sure the crew stays healthy.

        • Correct, and this is meant to attract the same investors and Bulls that already think Mars colonies is a solved problem, just need a few more years to run some tests. As with all, it is only about making himself richer.
        • Nobody colonizing Mars. Get real. The most likely outcome, is him landing on a cell when the full Epstein files come out.
          • The most likely outcome is that no one will be punished for anything in the Epstein files.
        • > colonize mars

          Oh, that crap again.

    • I don’t believe you’ve considered the possibility of a data center on Pluto…

      But in all seriousness, if there is a possibility of building industrial centers outside of the Earth’s atmosphere, it is surely not here yet. Lots of areas would need improvement.

    • What in particular is wrong/misleading in the Starcloud whitepaper, then?

      https://starcloudinc.github.io/wp.pdf

      • In Table 1, the cost of cooling of a terrestrial data centre is listed as $7M. The cost of cooling in space is assigned a value of $0 with the claim:

        "More efficient cooling architecture taking advantage of higher ΔT in space"

        My bold claim: The cost of cooling will not be $0. The cost of launching that cooling into space will also not be $0. The cost of maintaining that mechanically complex cooling in space will not be $0.

        They then throw in enough unrealistic calculations later in the "paper" to show that they thought about the actual cost at least a little bit. Apparently just enough to conclude that it's so massive there's no way they're going to list it in the table. Table 1 is pure fantasy.

        • That row specifically says "chiller energy cost" which is 0
      • Previous discussions on HN: - https://news.ycombinator.com/item?id=44390781

        - https://news.ycombinator.com/item?id=45667458

        - https://news.ycombinator.com/item?id=43977188

        I will not re-read them, but from what I recall from those threads is numbers don't make sense. Something like:

        - radiators the multiple square kilometers in size, in space;

        - lifting necessary payloads to space is multiples of magnitudes more than we have technology/capacity as the whole world now;

        - maintanence nightmare. yeah you can have redundancy, but no feasable way to maintain;

        - compare how much effort/energy/maintenance is required to have ISS or Tiangong space stations - these space datacenters sound ridiculous;

        NB: I would be happy to be proven wrong. There are many things that are possible if we would invest effort (and money) into it, akin to JFK's "We choose to go to the Moon" talk. Sounded incredible, but it was done from nearly zero to Moon landing in ~7 years. Though as much as I udnerstand - napkin math for such scale of space data centers seem to need efforts that are orders or magnitude more than Apollo mission, i.e. launching Saturn V for years multiple times per day. Even with booster reuse technology this seems literally incredible (not to mention fuel/material costs).

        • A giant space datacenter with square kilometers of solar panels doesn't make sense. A cluster of Starlink-sized satellites, which orbit near each other(1) and which are connected using laser-links might make sense.

          (1) There are orbital arrangements that allow satellites to stay close together with minimal orbital corrections. Scott Manley mentioned this in one of his videos.

          • Sounds like we would want to elevate from water wasting on Earth to pollution in space.
      • They do not at any point outline how cooling will be done, they simply say "it will be more efficient than chillers due to the larger delta T" which is incorrect because it's about dT not delta T
      • Probably this bit on page 4, which parent comment addresses: “More efficient cooling architecture taking advantage of higher ΔT in space.”
    • It’s funny how quickly the general public forgot about the “vacuum thermos”. (Perhaps more popular before StarBucks overran society).

      Those flasks don’t have any space age insulating material - mainly just a vacuum…

      Technology from 1892…

      • They are more popular than ever, actually. Pretty much all those fancy cups and bottles (like Stanley, other brands available) sold to keep your coffee hot/drink cold on the go are vaccum ones. It's just updated and more robust design compared to the older thermos flasks.
    • > It could be a legal dodge. It could be a power grab. What it will not be is a useful source of computing power

      It's a way to get cheap capital to get cool tech. (Personal opinion.)

      Like dark fibre in the 1990s, there will absolutely–someday–be a need for liquid-droplet radiators [1]. Nobody is funding it today. But if you stick a GPU on one end, maybe they will let you build a space station.

      [1] https://en.wikipedia.org/wiki/Liquid_droplet_radiator

    • As an engineer of the software variety, logically heat dissipation would seem like a difficult problem.

      But SpaceX has lots of real engineers who are very smart. I’m certain they ran the math on it. Which is more than you or I have done.

      If they say it can be done, I’m inclined to believe them.

      • Wow. Definitely not a textbook fallacy.

        I mean why think about anything, you know. Critical thinking is for losers, am I right?

    • I have reached the same conclusion -- this is perhaps not a distraction but an attempt to gather funds to pursue the One True Goal...
    • You can reject the heat by shedding hot mass, but only once.
      • Cooling by mass effect style yeeting hot chunks of metal out the back.

        Where will they go, nobody knows!

        • Depending on where they land, you can double the service you offer. AI computations coupled with rods from God.
        • When the radiation burns out a GPU, just dump as much heat into it as possible and yeet it into the atmosphere. Ez.
          • Goodness gracious, great balls of fire! (are raining down on my house)
            • Preferibly directly onto indian electronics salvagers
    • "But even if we stipulate that radiation, cooling, latency, and launch costs are all solved, other fundamental issues still make orbital data centers, at least as SpaceX understands them, a complete fantasy. "

      I'm pretty his point is that while cooling is an impossibility, it is not the only one!

    • He's got a trillion dollar compensation package on the line. You can absolutely guarantee he's doing something shady.
    • sam
      This is mistaken. In space a radiator can radiate to cold (2.7K) deep space. A thermos on earth cannot. The temperature difference between the inner and outer walls of the thermos is much lower and it’s the temperature difference which determines the rate of cooling.
      • "Radiate" is exactly what you have to do, and that is extremely slow. You need a huge area to dissipate the amount of power you are talking about.
        • Basically you concentrate the heat into a high emissivity high temperature material that’s facing deep space and is shaded. Radiators get dramatically smaller as temperature goes up because radiation scales as T⁴ (Stefan–Boltzmann). There are many cases in space where you need to radiate heat - see Kerbal Space Program
          • "High emissivity, high temperature" sounds good on paper, but to create that temperature gradient within your spacecraft the way you want costs a lot of energy. What you actually do is add a shit load of surface area to your spacecraft, give that whole thing a coating that improves its emissivity, and try your hardest to minimize the thermal gradient from the heat source (the hot part) throughout the radiator. Emissivity isn't going past 1 in that equation, and you're going to have a very hard time getting your radiator to be hotter than your heat source.

            Note that KSP is a game that fictionalizes a lot of things, and sizes of solar panels and radiators are one of those things.

      • I have a vacuum thermos. I've been unimpressed with its ability to keep coffee hot.
    • It links his middling AI company and his failing social media company with the only company that can send the United States to space.

      X failing and can't pay its debts? Welp, better give him a government bailout otherwise no more rockets for you!

      • This exactly. His other companies are failing. He links the shitty companies with the only one working.
    • The 4-5nm gpu will break from high energy protons from the sun.

      Lag for roundtrip: 35ms. But when satelite needs to pass through other satellites as has no ground coverage you add more lag and reduce bandwidth of the whole network.

      The best part is jurisdiction safety. Very hard to get raided by govs.

    • m463
      I used to really enjoy musk's talks when he was spooling up tesla. He was an engineer and obviously the world is missing what engineers see clearly.

      But now looking back and accounting for the claims he made there's a pattern.

      I saw this article:

      https://www.wired.com/story/theres-a-very-simple-pattern-to-...

      that said... he did jumpstart the EV industry. He has put up satellites every week for years. He is still a net benefit to all of us.

      • > he did jumpstart the EV industry.

        This is widely believed (especially in the US, where, other than the Leaf, most early electric cars never launched), but honestly pretty dubious. The first real electric cars, with significant production:

        2010 - Mitsubishi i-MiEV, Nissan Leaf

        2011 - Smart electric, Volvo C30 electric, Ford Focus electric, BYD e6.

        2012 - Renault Zoe (Renault launched a couple of other vehicles on the same platform ~2010, but they never saw significant production), Tesla Model S (Tesla had a prior car, the Roadster, but it never saw significant production).

        2013 - VW eUP, eGolf (VW occasionally put out an electric Golf historically, going back to 1992, but again those were never produced in large quantities).

        The big change ~2010 was around the economics of lithium ion batteries; they finally got cheap enough that everyone started pulling their concept designs and small-scale demonstration models into full production.

      • dsl
        > he did jumpstart the EV industry. He has put up satellites every week for years. He is still a net benefit to all of us.

        Talk to any former SpaceX or Tesla employee. They will clue you in that both were successful in spite of Elon, not because of him.

        The Cybertruck was really the first product he saw to completion from his own design. And well...

        • I think you under appreciate him a bit here. No he's not a super genius. He's probably not even a good engineer. But he is a) a total a.hole and b) a tremendous bullshitter. There are circumstances in which you need such a person to succeed (see also Steve Jobs). He yelled at people for 10 years straight and he was crucial in facilitating capital to build these very capital intensive products. A regular smart person would absolutely not have succeeded, for these reasons.
          • > bullshitter

            why is lying at the edge of committing fraud so respected?

    • Exactly - satellites need to be cooled to prevent overheating that wouldn’t happen on earth.

      (Space doesn’t help in cooling GPUs in a satellite - space makes cooling worse)

    • I think it's possibly more informative to look at what happened with SolarCity and Tesla and contemplate if there's not a similar dynamic here.
    • "A satellite is, if nothing else, a fantastic thermos."

      A satellite is quite unlike a thermos in the sense that it is carefully tuned to keep its temperature within a relatively narrow band around room temperature.[1] during all operational phases.

      This is because, despite intended space usage, devices and parts are usually tested and qualified for temperature limits around room temperature.

      [1] "Room temperature" is actually a technical term meaning 20°C (exceptions in some fields and industries confirm the rule).

    • AI sovereignty, not AI efficiency. Redesign AI chips with lower power density and higher thermal tolerances and you get more efficient radiation with some sacrifice in compute power. But you are outside the jurisdiction of every country.

      Then you get people paying much more money to use less-tightly-moderated space-based AI rather than heavily moderated AI.

    • The only way I see this actually working given the resource requirement is delta-v style with in orbit resource extraction using robots. By transferring heat to asteroids in the shade of the solar panels at L1 or something.

      https://share.google/uXWQyAp7a8nE03qoi

    • > Musk is up to something here. This could be another hyperloop (i.e. A distracting promise meant to sabotage competition). It could be a legal dodge. It could be a power grab. What it will not be is a useful source of computing power. Anyone who takes this venture seriously is probably going to be burned.

      That.

      Also, am I the only one to remember when SpaceX was supposed to pivot to transporting people from cities to cities, given how cheap and reusable and sure BFF/Starship was going to be ?

      Or how we were all going to earn money by pooling our full self driving cars in a network of robo taxis ?

      In all seriousness, what is the number of "unrealized sci-fi pipe dreams" that is acceptable from the owner a company ? Or, to be fair, what is the acceptable ratio of "pipe dreams" / "actually impressive stuff actually delivered (reusable rockets, starlink, decent EVs, etc...)" ?

    • Can’t you heat exchange inside the satellite, and make one part of the satellite incredibly hot so that it radiates a lot and dissipates.

      This is just a question. I have no expertise at all with this.

      • Yes, but you need energy to pump heat, and that has an efficiency maximum (thx ~~Obama~~ Carnot), and radiative cooling scales with the ~4th power of the temperature, so it has to be really hot, and so it requires a lot of energy to "cool down" the already relatively cool side and use that "heat" to heat up the other side that's a thousand degree hotter.

        All in all, the cooling system would likely consume more energy than the compute parts.

      • yes. it is how sats currently handle this. its actually exponentially effective too P = E S A T^4

        requires a lot of weight (cooling fluid). requires a lot of materials science (dont want to burn out radiator). requires a lot of moving parts (sun shutters if your orbit ever faces the sun - radiator is going to be both ways).

        so that sounds all well and good (wow! 4th power efficiency!) but it's still insanely expensive and if your radiator solution fucks up in any way (in famously easy to service environment space) then your entire investment is toast

        now i havent run the math on cost or what elon thinks the cost is, but my extremely favorable back of hand math suggests he's full of it

        • Be careful with the math there. While a 4th power is awesome you got the Stefan-Boltzman constant to consider and that's on the order of 10^-8

          Radiative power is really efficient for hot things but not so great when you're trying to keep things down to normal levels. Efficient for shedding heat from a sun but not so much for keeping a cpu from overheating...

        • Pet peeve:

          T^4 is not exponential in T, it’s polynomial. For exponential, T must be in the exponent, e.g. 2^T or so.

          Still, pretty effective.

          Having said that, agree that Elon is full of it.

          • yes sorry, it's a fourth order exponent but not exponential
      • Good intuition, that is generally how radiators work in space.
      • You can. This is how it is currently done, but it is not easy. It needs to have a large enough surface area to radiate the heat, and also be protected from the sun (as to not collect extra heat). For a data centre, think of an at least 1000m2 heat exchange panel (likely more to train a frontier model).
      • Sure but if it was a good idea we could do it on earth too and datacenters could stop gurgling a city worth of water
      • You definitely _can_ the question is, can you do it by enough for a reasonable amount of money. There are a few techniques to this but at the end of the day you need to radiate away, the heat otherwise it will just keep growing. You cannot keep pumping energy into the satellite without distributing the same amount back out again.
      • yeah if you want a heat thruster
      • >>This is just a question. I have no expertise at all with this.

        On the similar lines, why can't one run a refrigerator in space?

        • You can, but the heat needs to go somewhere, and now you're back to square one, with "how do I get rid of all this heat". Earth refrigerators have a large heat exchanger on the back for this purpose. In fact now you need to get rid of both of the heat your compute generates and the energy your refrigerator pump uses - an example people often give is that a fridge with an open door actually heats the room, as it spends energy on moving heat around pointlessly.
    • >i.e. The lack-of-a-thing that makes a thermos great at keeping your drink hot

      e.g. the lack-of-a-thing that makes a thermos great at keeping your drink cold too

      • At risk of stating the obvious - computers produce heat. "Keeping them cool" really means dissipating that heat. Insulating them will cause them to get hotter.
      • Yes but in this case the lack-of-a-thing keeps GPUs hot
        • people who do understand thermodynamics will already understand the problem, but innocent people who don't understand thermodynamics should not be misled by poorly chosen examples presented as proof.
    • You're thinking of outer space. At any distance away from earth where space is so thin that heat dissipation is impossible, then the speed of light will be prohibitive of any workloads to/from space. there is plenty of altitude above the karman line where there is enough atmosphere to dissipate heat. Furthermore, i don't know if they figured it out, but radiation can dissipate heat, that's how we get heat from the sun. Also, given enough input energy (the sun), active closed-cooling systems might be feasible.

      https://www.nasa.gov/smallsat-institute/sst-soa/thermal-cont...

      But I really hope posts like this don't discourage whoever is investing in this. The problems are solvable, and someone is trying to solve them, that's all that matters. My only concern is the latency, but starlink seems to manage somehow.

      Also, a matter of technicality (or so I've heard it said) is that the earth itself doesn't dissipate heat, it transforms or transfers entropy.

      • > At any distance away from earth where space is so thin that heat dissipation is impossible, then the speed of light will be prohibitive of any workloads to/from space.

        Why would they need to get data back to earth for near real time workloads? What we should be thinking about is how these things will operate in space and communicate with each other and whoever else is in space. The Earth is just ancient history

        • I feel like this is an incredibly fantastic goal-post-moving from the original announcement.

          SpaceX: "we're going to put datacenters in space"

          HN comments: "obviously we'll need to move human civilization into space first for this to make sense. checks out."

          • I wasn’t responding to the original announcement, I was responding to someone who presumed that these data centers need to send data back to earth.

            I was making a snide comment that certain ultra wealthy people don’t need these data centers to send data to earth, because they don’t plan on being here.

            • Ah. Apologies, that went right over my head!
              • All good haha I didn’t do a good enough job with it :)
    • My guess is it’s just another example of his habit of trying to use one of his companies to manufacture demand for another of his companies’ products.

      Specifically: Starship makes no economic sense. There simply isn’t any pre-existing demand for the kind of heavy lift capacity and cadence that Starship is designed to deliver. Nor is there anyone who isn’t currently launching heavy payloads to LEO but the only thing holding them back is that they need weekly launches because their use case demands a whole lot of heavy stuff in space on a tight schedule and that’s an all-or-nothing thing for them.

      So nobody else has a reason to buy 50 Starship launches per year. And the planned Starlink satellites are already mostly in orbit. So what do you do? Just sell Starship to xAI, the same way he fixed Cybertruck’s demand problem by selling heaps of them to SpaceX.

      • There might be a lot of induced demand from starship. I’m sure defense is a big one.
        • No, but really, where will it come from?

          If (as seems to be the case) nobody can identify a specific source of latent demand that is large enough to soak up the two order of magnitude increase in the supply of heavy lift launch capacity that Elon wants to deliver, then that strongly suggests that SpaceX does not actually have a business plan for Starship. Or at least, not a business plan that’s been thought through as clearly as a $5 billion (and counting) investment would warrant.

          “Defense” is not nearly specific enough to count as an answer. What kind of defense application, specifically, do you have in mind, and why does it need specifically this kind of heavy lift capacity to be viable?

      • >Specifically: Starship makes no economic sense.

        Starship can replace Falcon 9 and probably be cheaper, if fully reusable, so more profitable. So at least some economic sense is there already.

        • I have noticed that there are two radically different approaches to assessing Starship.

          One is based on boring old analysis, hard numbers, and, worst of all, continually updating the analysis as more information (e.g., Raptor’s severe expectations vs reality shortfall) becomes available. People who use this approach don’t seem to have an opinion of Starship that is trending upward.

          The other approach seems to be based on vibes, and trusting that Starship will meet its original design goals despite the fact that no rocket project has ever come close to such an achievement. If there’s ever any introspection about why Starship should be the exceptional project that actually does meet its performance goals, the conclusion tends to be something about how Starship is special because it’s being developed by a private company. And I’ve noticed that, if the conversation does get to this point, you can send it in all sorts of unpredictable and fascinating directions by saying words like “OTRAG” and “Conestoga.”

        • No, that's not how any of this works. Try to think for a moment why we still overwhelmingly use non-jumbo jets for aviation in a world where jumbo jets exist.
          • Not to mention that making the upper stage and payload fairing much bigger and heavier juat so you can recover them is not an automatic win. You can recover it, but you’ve also made it much more expensive in the first place. And the booster needs to be bigger, heavier and more expensive, too.

            It’s not an automatic deal breaker, of course. Falcon 9 is obviously a promising success. But Starship is also working with some new challenges that Falcon 9 didn’t have to worry about.

            Many of these stem from design compromises that were forced by Starship’s secondary goal of being capable of a trip to Mars. In that respect, it very much resembles another major project to produce a heavy launch vehicle with a reusable combination payload fairing and upper stage that is also capable of carrying a human crew: the Space Shuttle.

    • > It makes far more sense to build data centers in the arctic.

      Unfortunately no. The arctic region is too cold and humid. You need way more energy to manage the cooling of a datacenter there than somewhere hotter.

    • I have no idea how it compares to the heat being generated, but one advantage of space would be totally efficient radiative cooling, I believe. Assuming you can pump the heat, and can deploy a large enough surface area (the key question I assume), then you have that at least.
    • I suspect Musk has a workable plan of some sort, realistically. Clearly, the one thing that is available in space is an abundance of square meters. There is no need whatsoever to conserve space at sufficient orbit. It is a little counter intuitive as we are so used to needing to conserve all the things.

      Power input and heat radiation both scale with area so maybe there is some way to achieve this at scale. For instance, maybe it will not look like a traditional data center or even traditional chips.

      • The rumor I heard is that Musk's big issue with SpaceX was that he was only able to employ US citizens with a security clearance, as per the limitations of a rocket company, which he has rallied against multiple times.

        One of the motivations behind this whole thing could be that he could make a way for foreign talent to work on space projects without the necessary government signoff.

        • Would that really be that much of an unlock?
          • Yes. I don't have an estimate right off the bat, but if you considered all the people employed at top tech companies, what percentage do you think are US nationals eligible for a security clearance?

            I'd say less than a third.

            • I had a look at SpaceX career page. There are 128 software related roles available. Perhaps half of those could be filled by big tech type companies, the others are more specialized (like antenna software engineer). I don't think that 64 open positions would move the needle really. And, if it were that easy to get around the security clearance by having another company, he could have created a new / separate company years ago.

              Wouldn't a simpler explanation be that SpaceX is making a lot of money while xAI is losing a lot. If funds have to flow through Elon personally it is likely complicated and costly. Also, if the "space data center" idea is actually workable (I have no idea if it is) then it does make some logical sense as well. Of course, Twitter just seems like kind of a write off to me at this point.

    • > I would not assume cooling has been worked out.

      That's wise.

      However, TFA's purpose in assuming cooling (and other difficulties) have been worked out (even though they most definitely have not) was to talk about other things that make orbital datacenters in space economically dubious. As mentioned:

        But even if we stipulate that radiation, cooling, latency, and launch costs are all solved, other fundamental issues still make orbital data centers, at least as SpaceX understands them, a complete fantasy. Three in particular come to mind:
    • > Musk is up to something here. This could be another hyperloop (i.e. A distracting promise meant to sabotage competition). It could be a legal dodge. It could be a power grab.

      It could also just be ignorance and talking out of his ass to look smart. Like when he took over Twitter and began publicly spewing wrong technical details as if he knew what he was talking about and being corrected by the people actually working on the product.

    • or perhaps as simple as saving xAI for himself as he prepares to offload rest of Twitter?
    • > Musk is up to something here.

      This is Musk, yet again, pulling themes from sci-fi books. He has that vision of ushering in the "future" which is good for dragging us forward but also he fails a lot. His open letter cited the Kardashev scale and his vision for getting us forward like in the novel accelerando.

    • The ideal would be to park the data centers at the lagrange point behind the Earth in its umbra, so they don't need to dissipate direct solar heat.
    • Musk lies with ease and routinely. This and Optimus are both just more examples of that.
    • He goes on about putting a mass driver on the moon for ultra-low-cost space launches.

      His plan here clearly hinges around using robots to create a fully-automated GPU manufacturing and launch facility on the moon. Not launching any meaningful number from earth.

      Raises some big questions about whether there are actually sufficient materials for GPU manufacture on the moon... But, whatever the case, the current pitch of earth-launches that the people involved with this "space datacenter" thing are making is a lie. I think it just sounds better than outright saying "we're going to build a self-replicating robot factory on the moon", and we are in the age of lying.

      • If any single country tried to create a whole production chain to single-handedly manufacture modern computer equipment it would be on the order of decades to see any result. Doing it on the moon is just not realistic this century, maybe the next one. Although i don't think the economics would ever work out.
        • Do you acknowledge how much change was there in the XX century? How can you probably make such predictions with such confidence?
    • Yeah the Space Data Center companies completely gloss over this fact by saying "oh yeah and we'll need radiators 10x the size of our solar panels. NBD."
    • Its not just cooling thats totally not worked out, its internal networking, its power management (what happens when its in darkness?) how do you certify servers for +/-10g vibration (https://www.ralspace.stfc.ac.uk/Pages/Dynamics-and-vibration...)

      What about gamma rays? there is a reason why "space hardened" microcontrollers are MIPS chips from the 90s on massive dies with a huge wedge of metal on it. You can't just take a normal 4micron die and yeet it into space and have done with it.

      Then there is the downlink. If you want low latency, then you need to be in Low earth orbit. That means that you'll spend >40% of your time in darkness. So not only do you need to have a MAssive heat exchanger and liquid cooling loop, which is space rated, you need to have ?20mwhr of battery as well (also cooled/heated because swinging +/- 140 C every 90 minutes is not going to make them happy)

      Then there is data consistency, is this inference only? or are we expecting to have a mesh network that can do whole "datacentre" cache coherence? because I have bad news for you if you're going to try that.

      Its just complete and total bollocks.

      utter utter bollocks.

      • You don't put it in a standard orbit, you put it in a polar orbit with near 100% suntime ... obviously.

        Obviously you use the backside of the massive area of PV you need, for an equally massive area for HOPG radiator films with condensor coils (because obviously you use heatpumps for cooling, not pure liquid).

        Consider the obvious ways you'd actually do it, not the most naive ways.

        The GPU pods obviously won't weigh the same as a terrestrial rack. Space based solar arrays obviously don't weigh the same as your hail and storm resistant panels on your roof (see ROSA, but there might be another 10x weight reduction if using flexible solar in tension from rotation). Noone cares about a couple 100 ms extra for first token.

        Solar wind and drag are in my opinion the biggest issue. Problem : it's a giant surface catching drag and solar wind. Solution : it's a giant solar sail. Controlling the angle of PV for useful thrust, that's never really been done for a satellite.

    • > It makes far more sense to build data centers in the arctic

      This. Like it would make far more sense to colonize the poles than Mars.

    • apocalyptic space twitter with satellites shaped like whales that drop from the sky would have been cooler.
    • It's not just Musk, Google is working on it too... very soon to actually launch tests. I have a feeling it's a regulatory dodge of some kind.
    • You can't exchange heat with vacuum

      If you put a pipe with hot gas inside, in space, it will get colder by convection.

      Blow air through the pipe.

      • ok. your pipe is full. now what
    • The equation has a ^4 to the temperature. If you raise the temperature of your radiator by ~50 degrees you double its emission capacity. This is well within the range of specialised phase change compressors, aka fancy air conditioning pumps.

      Next up in the equation is surface emissivity which we’ve got a lot of experience in the automotive sector.

      And finally surface area, once again, getting quite good here with nanotechnology.

      Yes he’s distracting, no it’s not as impossible as many people think.

      • > And finally surface area, once again, getting quite good here with nanotechnology.

        So your hot thing is radiating directly onto the next hot thing over, the one that also needs to cool down?

      • > aka fancy air conditioning pumps

        Yeah, pumps, tubes, and fluids are some of the worst things to add to a satellite. It's probably cheaper to use more radiators.

        Maybe it's possible to make something economical with Peltier elements. But it's still not even a budget problem yet, it's not plainly not viable.

        > getting quite good here with nanotechnology

        Small features and fractal surfaces are useless here.

        • Peltiers and heat pipes don't remove heat, they just move it. You still need the radiator.
        • My dude, heat pipes were invented for satellites and there’s people walking around with piezo pumps in their phones these days. We’re getting close.

          Peltiers generate a lot of heat to get the job done so even though electricity is pretty much free, probably not a sure bet.

      • Raise the temperature of your radiator by 50 degrees and you double its emission capacity. Or put your radiator in the atmosphere and multiply its heat exchange capacity by a factor of a thousand.

        It's not physically impossible. Of course not. It's been done thousands of times already. But it doesn't make any economic sense. It's like putting a McDonald's at the top of Everest. Is it possible? Of course. Is it worth the enormous difficulty and expense to put one there? Not even a little.

        • For thousands of years we never even looked to Mount Everest, then some bloke on the fiver said he’d give it a shot. Nowadays anyone with the cash and commitment can get the job done.

          Same with datacenters in space, not today, but in 1000 years definitely, 100 surely, 10?

          As for the economics, it makes about as much sense as running jet engines at full tilt to power them.

          • > some bloke on the fiver said he’d give it a shot

            Hillary (he features on the NZ Five Dollar note) was one of those guys who does things for no good reason. He also went to both poles. This only tells us that it is indeed possible, but not that it's desirable or will become routine.

          • If we define a data center as a place where computers run primarily to serve distant users, then we've had data centers in space for decades.

            Nobody should doubt that it's possible, since it's been done. It just doesn't make any sense to do it purely for the sake of having computers do things that could be done on the ground.

            There's nothing weird about using jet engines to make electricity. The design of a turbine designed to generate thrust isn't necessarily that different from a turbine designed to generate electricity. You can buy a new Avon gas turbine generator today, the same engine used in the Canberra, Comet, Draken, and many others. It makes about a million times more economic sense than putting GPUs in space to run LLMs.

      • Even if you create a material with surface emissivity of 1.0:

        - let's say 8x 800W GPUs and neglect the CPU, that's 6400W

        - let's further assume the PSU is 100% efficient

        - let's also assume that you allow the server hardware to run at 77 degrees C, or 350K, which is already pretty hot for modern datacenter chips.

        Your radiator would need to dissipate those 6400W, requiring it to be almost 8 square meters in size. That's a lot of launch mass. Adding 50 degrees will reduce your required area to only about 4.4 square meters with the consequence that chip temps will rise by 50 degrees also, putting them at 127 degrees C.

        No CPU I'm aware of can run at those temps for very long and most modern chips will start to self throttle above about 100

        • Hence the fancy air conditioning pumps
          • ... on satellites?
            • Yes, that’s what we’re talking about. Data centers in space.

              You put the cold side of the phase change on the internal cooling loop, step up the external cooling loop as high temp as you can and then circulate that through the radiators. You might even do this step up more than once.

              Imagine the data center like a box, you want it to be cold inside, and there’s a compressor, you use to transfer heat from inside to outside, the outside gets hot, inside cold. You then put a radiator on the back of the box and radiate the heat to the darkness of space.

              This is all very dependent on the biggest and cheapest rockets in the world but it’s a tradeoff of convenience and serviceability for unlimited free energy.

              • Why not use the unlimited free energy on terrestrial data centers then? You can use solar power as we speak, no?
                • Because the sun hides at night. Scientists have yet to figure out where he goes. Until that happens it’s not a great power source.
                  • Overprovision solar and add batteries for the night, then. Whatever amount of money and effort is required to make space data centers feasible (launching, cooling, etc) cannot possibly be lower than just building solar powered terrestrial data centers + batteries or alternative power sources. It is just not as sexy a story to sell to investors as magic space computers.
                  • What do the satellites do in earth's shadow?
      • This makes zero sense.
      • > Next up in the equation is surface emissivity which we’ve got a lot of experience in the automotive sector.

        My car doesn't spend too much time driving in vacuum, does yours?

        • Engine bays have a lot of design go into where to keep heat and where to get rid of it. You can look up thermal coatings and ceramics etc.
          • Sure and it all routes to dump the heat to...where again? A vacuum? Or to a radiator with a fan with some kind of cooler fluid/gas from the environment constantly flowing through it?

            Seems like quite a massive difference to ignore.

        • Let's just hope the person you are responding to isn't Elon Musk!
          • I wouldn't say that roadster isn't doing much driving but dang is it drifting!
    • “Musk is on to something here”? Really? Any high school student with a basic grasp of physics could explain that. But sure, the idiot billionaire nazi “is on to something”. That’s giving him too much credit.

      Of course it doesn’t fucking make sense to put data centers into space. Even if heating were solved somehow magically, server disks are veeery prone to fail and need replacement. Shoot a rocket up every week to replace failed drives or absolutely burned through GPUs? Yeah, that doesn’t even remotely sound feasible.

      • Unless you want cash-rich AI companies to pay a certain company for weekly / daily lifts during the build-out phase. Eventual crash be damned, make hay while the sun shines
        • And burn even more energy and fuel than DCs on the ground, great idea :D
          • Nobody said it was a good idea except his accountant, who doesn't pay the energy bills.
    • I think Musk is backed into a corner financially. Most of his companies don't have that much revenue and their worth is mostly based on hope.

      They might be closer to collapsing than most people think. It's not unheard of that a billionaires net worth drops to zero over night.

      I think it's mostly financial reasons why they merged the companies, this space datacenter idea was born to justify the merge of SpaceX and xAI. To give investors hope, not to really do it.

    • All of this and more.

      For example: quite apart from the fact of how much rocket fuel is it going to take to haul all this shit up there at the kind of scale that would make these space data centres even remotely worthwhile.

      I'm not against space travel or space exploration, or putting useful satellites in orbit, or the advancement of science or anything like that - quite the opposite in fact, I love all this stuff. But it has to be for something that matters.

      Not for some deranged billionaire's boondoggle that makes no sense. I am so inexpressibly tired of all these guys and their stupid, arrogant, high-handed schemes.

      Because rocket fuels are extremely toxic and the environmental impact of pointlessly burning a vast quantity of rocket fuel for something as nonsensical as data centres in space will be appalling.

      • Starship is fueled with methane (natural gas) and liquid oxygen which aren't toxic. It does produce a lot of CO2 which is a problem with lots of flights.
        • IIRC the methane is produced at launch site with considerable pollution
      • Does that emit more than Elon's terrestrial data centers powered by natural gas, per unit of compute?
    • The materialist take is that his plan is to eventually over-value and then trade on his company valuations, and also have another merger lined up for future personal financial bailouts.
    • > You can't exchange heat with vacuum. You can only radiate heat into it.

      I don’t remember the difference from my science classes, isn’t This the same thing essentially?

      • The other two methods of heat transfer apart from radiation are conduction (through “touch”, adjacent molecules, eg from the outside of a chicken on the BBQ to the inside) and convection (through movement, eg cold air or water flowing past).
    • quantum computers on the sun!
    • Not going to read the article, because Data centers in space = DOA is common sense to me, however, did the article really claim cooling wasn't an issue? Do they not understand the laws of thermodynamics, physics, etc?

      Sure, space is cold. Good luck cooling your gear with a vacuum.

      Don't even get me started on radiation, or even lack of gravity when it comes to trying to run high powered compute in space. If you think you are just going to plop a 1-4U server up there designed for use on earth, you are going to have some very interesting problems pop up. Anything not hardened for space is going to have a very high error/failure rate, and that includes anything socketed...

      • > Not going to read the article, because Data centers in space = DOA is common sense to me, however, did the article really claim cooling wasn't an issue?

        No. Nearly everyone that talks about data centers in space talks about cooling. The point of this article was to talk about other problems that would remain even if the most commonly talked about problems were solved.

        It says:

        > But even if we stipulate that radiation, cooling, latency, and launch costs are all solved, other fundamental issues still make orbital data centers, at least as SpaceX understands them, a complete fantasy.

        and then talks about some of those other issues.

    • Jeffrey Epstein's friend Elon Musk is trying to stop a financial disaster in xAi that would expose how irresponsible he is. He's gonna put all that in a company that has real money coming from government and soon will get retail investors money.
    • Not disagreeing with you at all: that physics fact always come up. My honest question is: if it's a perfect thermos, what does, for example, the ISS do with the heat generated by computers and humans burning calories? The ISS is equipped with a mechanism to radiate excess heat into space? Or is the ISS slowly heating up but it's not a problem?
      • Massive radiators. In this photo[0], all of the light gray panels are thermal radiators. Note how they are nearly as large as the solar panels, which gives you an idea about the scale needed to radiate away 3-12 people's worth of heat (~1200 watts) + the heat generated by equipment.

        [0] https://images-assets.nasa.gov/image/jsc2021e064215_alt/jsc2...

        • The ISS is designed to emit 126kW of heat radiation between the active cooking systems and the solar array cooling system.
          • Which is less than a single rack of GPUs.
        • I agree, all the good papers definitely talk about custom designed radiators being used on the dark sides of data center in space.
      • The ISS has giant heat sinks[1]. Those heat sinks are necessary for just the modest heat generated on the ISS, and should give an idea of what a sattelite full of GPU's might require...

        [1] https://en.wikipedia.org/wiki/External_Active_Thermal_Contro...

      • The ISS has MASSIVE radiators. Most of its volume is radiator. 900 cubic meters of space 2500 square meters of radiator.
      • The TL;DR is they radiate it into space via large, high surface area arms that stick out of the station.
    • It will be the communications, not the compute part.
    • One man able to put a data center worth of mass in orbit is one man able to crash a datacenter worth of mass into Earth anywhere he wants.
      • Not a given. Re enter the atmosphere. Sure. Avoid vaporization? Much harder problem.
        • I think it's actually the other way around, satellites need to be specifically designed to burn up fast in the atmosphere. See for example the warnings about space debris from Chinese satellites not designed with this in mind.
        • There is some evidence to suggest that spacex knows how to reenter an object without burning it up.
        • 100 tons of steel will not vaporize before it hits the ground
    • A glaring lack of oceans to boil
    • I think people underestimate how quickly heat radiates to space. A rock in orbit around Earth will experience 250F/125C on the side facing the Sun, and -173C/-280F on the other side. The ability to rotate an insulating shield toward the sun means you're always radiating.
      • I think you may be overestimating how quickly this happens and underestimating how much surface area that rock has. Given no atmosphere, the fact that the rock with 1/4 the radius of Earth has a temperature differential of only 300C between the hot side and the cold side, there's not a lot of radiation happening.

        In deep space (no incident power) you need roughly 2000 sq meters of surface area per megawatt if you want to keep it at 40C. That would mean your 100 MW deep space datacenter (a small datacenter by AI standards) needs 200000 sq meters of surface area to dissipate your heat. That is a flat panel that has a side length of 300 meters (you radiate on both sides).

        Unfortunately, you also need to get that power from the sun, and that will take a square with a 500 meter side length. That solar panel is only about 30% efficient, so it needs a heatsink for the 70% of incident power that becomes heat. That heatsink is another radiator. It turns out, we need to radiate a total of ~350 MW of heat to compute with 100 MW, giving a total heatsink side length of a bit under 600 meters.

        All in, separate from the computers and assuming no losses from there, you need a 500x500 meter solar panel and a 600x600 meter radiator just for power and heat management on a relatively small compute cluster.

        This sounds small compared to things built on Earth, but it's huge compared to anything that has been sent to space before. The ISS is about 100 meters across and about 30 meters wide for comparison.

        • First, thanks for your knowledgeable input.

          Second, are you saying that we basically need to have a radiator as big (approximately) as the solar panels?

          That is a lot, but it does sound manageable, in the sense that it approximately doubles what we require anyway for power.

          So, not saying that it’s easy or feasible, but saying that cooling then seems “just” as difficult as power, not insurmountably more difficult. (Note that the article lists cooling, radiation, latency, and launch costs as known hard problems, but not power.)

          • > So, not saying that it’s easy or feasible, but saying that cooling then seems “just” as difficult as power, not insurmountably more difficult

            This is with an ideal radiator and perfect pointing so it receives no incident light, so in practice you need a bigger one than this.

            However, if you think launching a solar panel that is the size of 10 NYC city blocks is "manageable," then why not throw in a radiator that is about 15 city blocks in size?

        • What do you think about droplet radiators? E.g. using a ferrofluid with magnetic containment for capture and enough spare on board to last five years of loss due to occasional splashes?
        • > 2000 sq meters of surface area per megawatt if you want to keep it at 40C

          What is this figure based on?

        • > it's huge compared to anything that has been sent to space before

          That is the goal of Starship though. The ISS has a mass of 400 ton, the goal is to need only two cheap launches of Starship v4 for that.

    • > It makes far more sense to build data centers in the arctic.

      Please, no!

    • I want to nitpick you here but a thermos is specifically good at insulating because not only does it have a vacuum gap, it's also got two layers of metal (inner and outer) to absorb and reflect thermal radiation.

      That specific aspect is NOT true in space because there's nothing stopping thermal radiation.

      Now you're correct that you can't remove heat by conduction or convection in space, but it's not that hard to radiate away energy in space. In fact rocket engine nozzle extensions of rocket upper stages depend on thermal radiation to avoid melting. They glow cherry red and emit a lot of energy.

      By Stefan–Boltzmann law, thermal radiation goes up with temperature to the 4th power. If you use a coolant that lets your radiator glow you can conduct heat away very efficiently. This is generally problematic to do on Earth because of the danger of such a thing and also because such heat would cause significant chemical reactions of the radiator with our corrosive oxygen atmosphere.

      Even without making them super hot, there's already significant energy density on SpaceX's satellites. They're at around 75 kW of energy generation that needs to be radiated away.

      And on your final statement, hyperloop was not used as a "distraction" as he never even funded it. He had been talking about it for years and years until fanboys on twitter finally talked him into releasing that hastily put together white paper. The various hyperloop companies out there never had any investment from him.

      • > a thermos is specifically good at insulating because not only does it have a vacuum gap, it's also got two layers of metal (inner and outer) to absorb and reflect thermal radiation.

        Not necessarily. There are many modern thermos "cups" that are just a regular cup, except with two layers of glass and a vacuum. Even the top is open all the time. (e.g. https://www.ikea.com/us/en/p/passerad-double-wall-glass-8054... )

        It's still good enough to keep your coffee hot for an entire day.

      • It is well known that Musk primary reason to push Hyperloop was because he didn’t want them to build a high speed rail for some reason:

        > Musk admitted to his biographer Ashlee Vance that Hyperloop was all about trying to get legislators to cancel plans for high-speed rail in California—even though he had no plans to build it.

        https://time.com/6203815/elon-musk-flaws-billionaire-visions...

    • musk is always up to something but remarkably people still eat this stuff up - remarkable to watch!
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      • There are several companies working on this, and the first generation tech is already proven, working in space on the ISS. Even Paul G is on board. https://x.com/paulg/status/2009686627506065779?s=20
        • Of course it's working. We've had computers operating in space for decades. There's no doubt it can be done.

          The question isn't whether it's possible, the question is why you'd do it just for data centers. We put computers in space because they're needed to do things that can only be done from there. Data centers work just fine on the ground. What's so great about data centers in space that makes them worth the immense cost and difficulty.

          I know a lot of prominent people are talking about this. I do not understand it. pg says "when you look at the tradeoffs" well what exactly is he looking at? Because when I look at the tradeoffs, the whole concept makes no damned sense. Sure, you can put a bunch of GPUs in space. But why would you do that when you can put them in a building for orders of magnitude less money?

        • https://xcancel.com/paulg/status/2009704615508586811#m for those who don't partake.

          I liked one comment someone made: if it's just about dodging regulation, then put the data centers on container ships. At any given time, there are thousands of them sailing in international waters, and I'm sure their operators would love to gain that business.

          That being said, space would be a good place to move heat around with Peltier elements. A lot of the criticisms revolve around the substantial amount of coolant plumbing that will be needed, but that may not necessarily be what SpaceX has in mind.

    • > I would not assume cooling has been worked out.

      There should be some temperature where incoming radiation (sunlight) balances outgoing radiation (thermal IR). As long as you're ok with whatever that temperature is at our distance from the sun, I'd think the only real issue would be making sure your satellite has enough thermal conductivity.

    • The Stefan-Boltzmann Law tells us that radiative power scales to the fourth power of temperature (T^4). While terrestrial cooling is largely linear and dependent on ambient air/water temperature (the "wet-bulb" limit), a radiator in space is dumping heat into a 3-Kelvin sink. That thermal gradient is massive.
      • This is misleading: - A radiator only “sees” 3 K if it’s perfectly shielded from the Sun, Earth albedo, and Earth IR. In Earth orbit you can easily get hundreds of W/m^2 incident; without sunshields the net rejectable heat is greatly reduced. - You have a "massive" advantage only if the radiator is allowed to run very hot: At 300–310 K with \epsilon \approx 0.9: about 400–500 W/m^2. Effective "radiative heat transfer coefficient" at 300 K: h_rad \approx 4\epsilon\sigma T^3 \approx 5-6 W/m^2K. That's orders of magnitude lower than forced convection in air (\approx 50–500 W/m^2K) or the water side of a heat exchanger (>=1000 W/m^2K).
        • Yeah I took the best case scenario in space, I did not account for anything else. I imagine the space DC be like two sides, one is pointing towards the sun and being a solar panel the other is a cold radiator radiating heat into the void. I am not sure how feasible this is.
      • The thermal gradient in space is meaningless because there is hardly any matter to dump the energy into. This means you are entirely reliant on thermal radiation. If you look at the numbers given by Stefan-Boltzmann law you'd see that means to radiate a significant amount of energy you need a combination of a lot of surface area and high temperatures.

        This means you need some sort of heat pump. For a practical example you can look at the ISS, which has what they call the "External Active Thermal Control System" (EATCS), it's a complicated system and it provides 70kW of heat rejection. A datacenter in space would need to massively scale up such a system in order to cool itself.

        • The ISS comparison is a bit of a category mismatch. The EATCS is complex because it’s a life-support system that must keep humans at exactly 22C (295K) while managing ammonia loops in a manned environment.

          Computers aren't humans. High-performance silicon can comfortably operate at a junction temperature of 80C to 90C (approx. 360K). Because of that T^4 relationship, a radiator at 85C rejects nearly double the heat per square meter than a radiator at 20C, unless I miss something.

          So this makes it a bit more nuanced.

      • Stefan-Boltzmann is about absolute, not relative temperature.

        When one does the math on the operating temperatures of regular computing equipment that we use on Earth, how much heat it generates per watt, and how fast it would need to sink that heat to allow for continuous operation, one gets surface areas that are not impossible, but are pretty on the high end of anything we've ever built in space.

        And then you have to deflect the incoming light from the Sun which will be adding to your temperature (numbers published by private space companies regarding the tolerances of payloads those companies are willing to carry note that those payloads have to be tolerant of temperatures exceeding 100° C, from solar radiation alone). That is doable, you could sunshield the sensitive equipment and possibly decrease some of your thermal input load by putting your craft out near L2 which hangs out in the penumbra of Earth. Still a daunting technical challenge when the alternative is just build it on the planet with the technology and methods we already have.

        • You’re correct that Stefan-Boltzmann uses absolute temperature (K), but that only reinforces the advantage of moving the "hot side" of the gradient up. If you increase your radiator temp from 300K (standard Earth ambient) to 360K (hot silicon), your radiative efficiency doesn't just go up by 20%—it nearly doubles.

          The Solar Load is Directional: Unlike a terrestrial atmosphere where heat is omnidirectional, space allows for "shadow engineering." A simple multi-layer insulation (MLI) sunshield can reduce solar flux by orders of magnitude. We do this for the James Webb Space Telescope to keep instruments at 7K while the sun-facing side is at 380K. For a data center, you don't need 7K; you just need to keep the "dark side" radiators in the shade.

    • Space is a vacuum and yet here we are on a rock floating in space warmed by the sun and the temperate is actually pretty comfortable. Indeed, without the greenhouse effect it would be positively chilly. An important part of a thermos is that you have to use high albedo materials in the vacuum chamber or else it would lose heat too quickly to radiation.

      A satellite as a whole will come to thermal equilibrium with space at a fairly reasonable temperature, the problematic part is that the properties of electricity make it easy to concentrate a good part of the incoming energy in a small area where the GPU is. Heat is harder to move than electricity and getting that heat back out to the solar panels or radiators requires either heavy heat pipes or complex coolant pumps.

      • a data center in space doesn't have a gigantic rock taking up most of its area, a data center in space is 100% data center 0% rock.

        If it had the same data center to rock ratio as earth, it would just end up being earth in the end, and earth doesn't seem to be wanting to stick to its equilibrium either right now

        • The rock in this case acts as extra thermal mass that makes it take longer to reach thermal equilibrium, but doesn't change what the ultimate thermal equilibrium is. Only the configuration of the parts of the surface that can absorb or radiate electromagnetic radiation do that. And because rock is a fairly good insulator we only really benefit from the top layer and if the sun went out we would all freeze in a week or so.
          • it changes the amount of exposed area to release heat back into the universe. if you have a non-negligible amount of compute compared to earth, you are going to be approaching a non-negligible amount of space required to radiate that away, along with all the other costs and maintainability issues
            • The formula for the equilibrium temperature for a sphere in sunlight is

                  2 * pi * r^2 * L / (4 * pi * d) * (1 -a) = 4 * pi * r^2 * sigma * T^4
              
              As you can see there are pi*r^2 on both sides of the equation, the surface area to cross section ratio of a sphere doesn't change as it gets bigger and so the equilibrium temperature doesn't change no matter how big the sphere is. (d is the distance to the Sun, nothing to do with the sphere itself).
        • Well, they do have silicon, with some more additives they can make rocks in space! And throw them at earth, that will show em
    • >I would not assume cooling has been worked out

      On the other hand Starlink has several thousand satellites up there using solar power to run processors and cooling them with radiators so it's not totally new technology.

      Here's a Musk tweet linking some analysis https://x.com/elonmusk/status/2013676764099199156

  • I was talking to someone about this the other day. I was part of a team at NASA that developed a cooling system for the ISS and this whole premise makes no sense to me.

    1. Getting things to space is incredibly expensive

    2. Ingress/egress are almost always a major bottleneck - how is bandwidth cheaper in space?

    3. Chips must be “Rad-hard” - that is do more error correcting from ionizing radiation - there were entire teams at NASA dedicated to special hardware for this.

    4. Gravity and atmospheric pressure actually do wonders for easy cooling. Heat is not dissipated in space like we are all used to and you must burn additional energy trying to move the heat generated away from source.

    5. Energy production will be cheaper from earth due to mass manufacturing of necessary components in energy systems - space energy systems need novel technology where economies of scale are lost.

    Would love for someone to make the case for why it actually makes total sense, because it’s really hard to see for me!

    • It sounds hard but it shouldn't not make sense.

      1. Solving cost of launching mass has been the entire premise of SpaceX since day one and they have the track record.

      2. Ingress/egress aren't at all bottlenecks for inferencing. The bytes you get before you max out a context window are trivial, especially after compression. If you're thinking about latency, chat latencies are already quite high and there's going to be plenty of non-latency sensitive workloads in future (think coding agents left running for hours on their own inside sandboxes).

      3. This could be an issue, but inferencing can be tolerant to errors as it's already non-deterministic and models can 'recover' from bad tokens if there aren't too many of them. If you do immersion cooling then the coolant will protect the chips from radiation as well.

      4. There is probably plenty of scope to optimize space radiators. It was never a priority until now and is "just" an engineering problem.

      5. What mass manufacture? Energy production for AI datacenters is currently bottlenecked on Siemens and others refusing to ramp up production of combined cycle gas turbines. They're converting old jet engines into power plants to work around this bottleneck. Ground solar is simply not being considered by anyone in the industry because even at AI spending levels they can't store enough power in batteries to ride out the night or low power cloudy days. That's not an issue in space where the huge amount of Chinese PV overproduction can be used 24/7.

      • > There is probably plenty of scope to optimize space radiators. It was never a priority until now and is "just" an engineering problem.

        It's a physics problem, as others pointed out, but even if we take it as another "just an engineering problem", have a look at the Hyperloop. Which is similarly just a long vacuum tube, and inside is like an air hockey table, not that big a deal, right?...

        • Musk's companies never tried to make the hyperloop, they never even started on it. SpaceX is a bit different.
          • so spacex worked on an orbital data center?
            • no, just merely more satellites than the rest of the world combined, with the first functioning laser links in a large constellation.
      • 3. There are WAY more things to get corrupted on a computer system than tokens. And non-determinism does NOT mean it’s tolerant to faults. Random values are intentionally introduced at the right moment for LLMs.
      • > There is probably plenty of scope to optimize space radiators. It was never a priority until now and is "just" an engineering problem.

        Well, it's a physics problem. The engineering solution is possibly not cost efficient. I'd put a lot of money that it isn't.

        • That bit reminded me of someone who wanted us to design a patch the size of a small postage stamp, at most 0.2mm thick, so you could stick on products. It was to deliver power for two years of operation, run an LTE modem, a GNSS receiver, an MCU, temperature and humidity sensor and would cost $0.10. And it would send back telemetry twice per day.
          • 'A mere matter of engineering'.
            • The conversation went something like this (from memory):

              - We can't do that

              - Why not?

              - Well, physics for one.

              - What do you mean?

              - Well, at the very least we need to be able to emit enough RF-energy for a mobile base station to be able to detect it and allow itself to be convinced it is seeing valid signaling.

              - Yes?

              - The battery technology that fits within your constraints doesn't exist. Nevermind the electronics or antenna.

              - Can't you do something creative? We heard you were clever.

              I distinctly remember that last line. But I can't remember what my response was. It was probably something along the lines of "if I were that clever I'd be at home polishing my Nobel medal in physics".

              Even the sales guy who dragged me into this meeting couldn't keep it together. He spent the whole one hour drive back to the office muttering "can't you do something creative" and then laughing hysterically.

              I think the solution they went for was irreversible freeze and moisture indication stickers. Which was what I suggested they go for in the first 5 minutes of the meeting since that a) solved their problem, and b) is on the market, and c) can be had for the price point in bulk.

              • That's so hilarious. I've had a couple that went in that direction but nothing to come close.

                To be fair though, there is a lot of tech that to me seems like complete magic and yet it exists. SDR for instance, still has me baffled. Who ever thought you'd simply digitize the antenna signal and call it a day, hardware wise, the rest is just math, after all.

                When you get used to enough miracles like that without actually understanding any of it and suddenly the impossible might just sound reasonable.

                > Can't you do something creative? We heard you were clever.

                Should be chiseled in marble.

                • The purely digital neighborhood of the SDRs is much easier to explain than the analog rat droppings between the DAC/ADC and the antenna. That part belongs to dark wizards with costly instruments that draw unsettling polar plots, and whose only consistent output is a request for even pricier gear from companies whose names sound an awful lot like European folk duos.

                  The digital end of SDRs are simple. Sample it, then once you have trapped the signal in digital form beat the signal into submission with the stick labeled "linear algebra".

                  (Nevermind that the math may be demanding. Math books are nowhere near as scary as the Sacred Texts Of The Dark Wizards)

                  "Rohde & Schwarz — live at the VNA, 96 dB dynamic range, one night only."

                  • > whose names sound an awful lot like European folk duos.

                    That had me laughing out loud, you should have left the name out to make it more of a puzzler :)

                    I apparently have been drawn to the occult for a long time and feel more comfortable with coils, capacitors and transmission lines than I do with the math behind them. Of course it's great to be able to just say 'ridiculously steep bandpass filter here' and expect it to work but I know that building that same thing out of discrete components - even if the same math describes it - would run into various very real limitations soon.

                    And here I am on a budget SDR speccing a 10 Hz bandfilter and it just works. I know there must be some downside to this but for the life of me I can't find it.

            • All you need to do is make use of a higher dimension to pack stuff into. And then mass produce to bring costs down. How hard can that be?
              • Skippy the Magnificent will solve this for us.

                (reference to a character in the Expiditionary Force series by Craig Alanson

                Only a very small portion of his physical presence is in local spacetime, with the rest in higher spacetime. He can expand his physical presence from the size of an oil drum or shrink to the size of a lipstick tube. He can’t maintain that for long without risking catastrophic effects. If he did, he would lose containment, fully materialize in local spacetime and occupy local space equal to one quarter the size of Paradise. The resulting explosion would eventually be seen in the Andromeda Galaxy.)

        • Not only is it not cost-effective, it's pointless (in this context).

          Radiators works almost just as well on Earth. Convection and conduction more than make up the difference.

        • What makes you so sure? SpaceX already has thousands of 6 kW networking racks flying around in LEO and they dissipate their heat just fine, and are plenty cost-effective. You think they can't do any better than that with a new design specifically optimized for computing rather than networking?
          • Probably, but they likely can't do better than we can do on Earth. Networking in space offers specific advantages that are not easy to replicate on Earth. Data centers in space don't have clear advantages beyond easily debunked ideas about cooling and power.
            • I'm not talking about the whole idea, just the heat dissipation part. So many people in this thread seem so sure this is impossible because you can't radiate heat in space, completely ignorant to the fact that SpaceX is already dissipating over 20 MW of solar power in LEO in a reasonably cost-effective manner.

              The advantage of 24/7 solar power is clear, obvious, and undeniable, it's just a question of whether that's outweighed by the other disadvantages.

          • The solar panels on the newest satellites can deliver 6kW but the power that satellite actually uses is less. The satellite is only using 300W[1] during the dark phase of it's orbit when it can use it's entire mass to cool down. Is that limit because of the battery or is it because the satellite needs to radiate all the heat it acquired from the other half of the time in the sun?

            [1] https://lilibots.blogspot.com/2020/04/starlink-satellite-dim...

            • Looks like that's a purely speculative assumption the blog author made, not a fact. I'm not sure why he made that assumption given that Starlink doesn't actually stop working at night.

              Fair point that in SSO you'd need 2-3x the radiator area (and half the solar panels, and minimal/no batteries). I don't think that invalidates my point though.

      • “just an engineering problem”

        Sounds a bit like that Dilbert where the marketing guy has sold a new invisible computer and is telling the engineers to now do their job and actually make it.

      • > It sounds hard but it shouldn't not make sense.

        It does not make sense.

        The question isn't "can you mitigate the problems to some extent?", it's "can you see a path to making satellite data centers more appealing than terrestrial?"

        The answer is a flat out "no," and none of your statements contradict this.

        Terrestrial will always be better:

        1. Reducing the cost of launches is great, but it will never be as cheap as zero launches.

        2. Radio transmissions have equally high bandwidth from Earth, but fiber is a better network backbone in almost every way.

        3. Radiation events don't only cause unpredictable data errors, they can also cause circuit latch-ups and cascade into system failure. Error-free operation is still better in any case. Earth's magenetosphere and atmosphere give you radiation shielding for free, rad-hard chips will always cost more than standard (do they even exist for this application?), and extra shielding will always cost more than no shielding.

        4. On Earth you can use conduction, convection, AND radiation for cooling. Space only gets you marginally more effective radiation.

        5. Solar is cheaper on the ground than in space. The increase in solar collection capability per unit area in space doesn't offset the cost of launch: you can get 20kW of terrestrial solar collection for around the price of a single 1U satellite launch, and that solar production can be used on upgraded equipment in the future. Any solar you put on a satellite gets decommissioned when the inference hardware is obsolete.

        And this ignores other issues like hardware upgrades, troubleshooting, repairs, and recycling that are essentially impossible in space, but are trivial on the ground.

      • My lord a sensible comment her. A hearty upvote.
      • > Solving cost of launching mass has been the entire premise of SpaceX since day one and they have the track record.

        They have to solve for it being cheaper to launch and operate in space vs building and operating a datacenter with its own power generation on Earth.

      • I have no expertise is this area, so I'm not getting into whether or not this idea makes sense.

        That being said, this statement strikes me as missing the point:

        > Solving cost of launching mass has been the entire premise of SpaceX since day one and they have the track record.

        As I understand it, SpaceX has a good track record of putting things into space more cost effectively than other organisations that put things into space.

        That is not the benchmark here.

        It doesn't matter if Musk can run thousands of data centres in space more cost effectively than (for example) NASA could. It matters whether he can do it more cost effectively than running them on earth.

        • The cost of "launching" mass on Earth is not zero, though.
          • I didn't suggest that it was.
        • I don’t think that statement was missing the point. As you point out, what matters is the total cost of ownership of the system. The cost of launching mass into space today isn’t the only reason terrestrial data centers are more cost effective today, but it’s the main one. If you make it cheap enough to send giant solar arrays and radiators to space, the other costs of operating in space may start to look like a small price to pay to eliminate the need for inputs like land and batteries.
    • > Would love for someone to make the case for why it actually makes total sense, because it’s really hard to see for me!

      Elon musk has a history of making improbable-sounding promises (buy a tesla now, by 2018 it will be a self-driving robotaxi earning money while you sleep, humanoid robots, hyperloops).

      The majority of these promises have sounded cool enough to enough people that the stock associated with him (TSLA) has made people literal millionaires just by holding onto the stock, and more and more people have bought in and thus have a financial interest in Musk's ventures being seen in a good light (since TSLA stock does not go up or down based on tesla's performance, it goes up or down based on the vibes of elon musk. It is not a car company stock, it is an elon vibes check).

      The thing he's saying now pattern matches to be pretty similar, and so given Musk's goal is to gain money, and he gains money by TSLA and SpaceX stock going up, this makes perfect sense as a thing to say and even make minor motions towards in order to make him richer.

      People will support it too since it pattern matches with the thing prior TSLA holders got rich off of, and so people will want to keep the musk vibes high so that their own $tsla holdings go to the moon.

      Make sense now?

      • The story here is even simpler. SpaceX is going public this year. Elon made a monumentally shitty investment in Twitter and then poured a stupid amount of money into xAI at the peak of the cycle. By having SpaceX buy xAI, he gets to swap worthless shares in that company for more SpaceX liquidity. Simple as that.
        • Exactly, and there needs to be some economic justification for a giant rocket. There is no money to be made by going to Mars, and AI data centers in space could attract investors (who are just riding the data center hype).
          • > I data centers in space could attract investors (who are just riding the data center hype).

            I find this to be the most obvious game plan here. Makes total sense from financial engineering point of view.

            You _might_ get to develop nice tech/IP to enable other space based businesses at the same time. "we sold them on X but delivered Y". So it's a bit of a hail mary, but makes total sense to me if you want to have a large budget for inventing the future.

            Once you can demonstrate even a fraction of this capability of operations ... I think you can sell a "space dominance" offering to Pentagon for example and just keep pedaling.

            "We are going to build the perfect weapon" does not necessarily entice as large engineer population as "we are going to Star Trek".

            Another thing - if Moon is going to be a thing, then _properties on Moon_ are going to be a thing.

            In theories of value in post-ai societies scarce assets like land are going to become more valuable. So it's a long term plan that makes sense if you believe Moon will be a realestate market.

        • Really seems silly to think that the guy with $800 billion is spending most of his time maximizing his money.
          • Doesn't it just make sense though? How else would he have gotten 800 billion dollars?
          • Ah, this old fallacy. There are myriad examples of the rich striving to be richer and the powerful fighting to gain even more power. Why would it be any different with Musk? If anything I suspect (this is absolutely an unverifiable opinion; I am not stating it as fact) that Musk's driving force is to become the first trillionaire.
          • Welcome to billionares. If they weren't obsessed with "number go up" over any other consideration, they wouldn't be billionares.
            • Billionaire money is not like money for the normal person. It is a placeholder for how much influence you have on the economy - and even the state.

              It is not just a number, as it is for people who just save a few dollars, for whom it really is just a number until they withdraw money to use it. The billionaire's money is not "money", it is actual working assets, and the abstraction of turning this into a number does a terrible job, the result now misunderstood by many. Assets being companies doing stuff mostly (holding non-control-giving paper assets is different and not what being a top capitalist is about, only used as an additional tool below the actual goal). Which they fully control (the small investor does not even have any control worth mentioning when they own shares of a public company).

              They don't just play with money, they play with real things! And they want to play with ever bigger real things. They don't just want to improve some minor product. They want to control the fate of civilization.

              OT:

              I hate this money view with a passion, this is what too many people discussing wealth inequality issues get wrong. This is not Scrooge McDuck and his money pile. Money is an abstraction, and it is misused terribly, hiding what is actually going on for too many observers who then go on to discuss "numbers".

              That is also why the idea to "just redistribute the money of the rich" is a failure. It isn't money! It is actual real complex organizations. And you can't just make everything into a public company, and also, even when they are, for better or worse owners don't lead like managers. Doing the socialism thing (I grew up in the GDR) where everybody owns a tiny bit of everything just does not work the same.

              We will have to look at what those super-rich are actually doing, case by individual case of ownership, not just look at some abstract numbers. Sometimes concentrated control over a lot of assets is a good thing, and other times it is not. Ignoring the objection of "who would control that?", because right now they control themselves so it's never nobody.

              • I think you have read the "redistrubute the money" people wrong. They definitely, absolutely want to reduce the power the tiny minority hold over the many. That's the whole point. The money is a tool to get the work done.
          • He probably have 700 billion in loans and need to pay rent
          • What’s silly is a bunch of so-called intelligent entrepreneurs and tech insiders twisting themselves into a pretzel coming up with reasons why this or that won’t work, by the guy who keeps doing the impossible
            • > by the guy who keeps doing the impossible

              What exactly has Elon done that's "impossible"? Like the Boring Company where he promised 1,000x faster boring? It turned into a mile or two of a poorly routed hole with some Teslas tossed down into it. He and his shills hand waved away the problem, confident their brilliance would allow them to dig 1,000x faster than modern commercial boring. It never happened.

              The only impossible thing Elon has done is make fantasy claims and real people fall for it.

              • I will definitely credit Elon with building a company that made reusable self-landing rockets seem routine and boring. That was definitely "impossible".

                Pretty much everything else though is just vapourware.

                • > That was definitely "impossible".

                  It was impossible in the sense that nobody else did it before. It was not impossible as in you need to violate basic laws of Physics or elementary Economics.

                  Before reusable rockets, the idea made sense. Building a rocket is expensive; if we reuse we don’t have to keep spending that money. Fundamentally, rockets are rockets. It’s not like they invented anti-gravity or anything.

                  It’s like climbing the Everest. Before it was done, it was still something people could plan and prepare for. But you’re not going to climb all the way to the moon, even with oxygen bottles. It’s a completely different problem to solve.

                  The most difficult point to argue against for people who want to defend Musk’s delusions is simple economics: at the end of the day, when you’ve solved

                  - the energy source problem (difficult but probably doable);

                  - the radiation-resistant chips issue (we know we can do it, but the resulting chip is not going be anywhere near as fast as normal GPUs on Earth);

                  - the head dissipation problem (physically implausible, to be charitable, with current GPUs, but considering that a space-GPU would have a fraction of the power, it would just be very difficult);

                  - the satellite-to-satellite communication issue, because you cannot put the equivalent of a rack on a satellite, so you’d need communication to be more useful than a couple of GeForces (sure, lasers, but then that’s additional moving parts, it’s probably doable but still a bit of work);

                  - the logistics to send 1 million satellites (LOL is all I can say, that’s a fair number of orders of magnitude larger than what we can do, and a hell of a lot of energy to do it);

                  - and all the other tiny details, such as materials and logistics just to build the thing.

                  Then, you still end up with something which is orders of magnitude worse and orders of magnitude more expensive than what we can already do today on Earth. There is no upside.

      • Yeah, but landing a rocket backwards also sounded very improbable to me, yet it looks pretty cool now.

        Also people made fun of tesla that it will never be able to compete with the big carmakers. Now I would rather have some stocks in tesla than holding on to volkswagen.

        • I wouldn’t be so sure about Tesla stock. Tesla has only weathered 1 market downturn cycle and that was when it was a very different company. The company has thus far had access to plentiful capital since the Model S started being delivered.

          Famous investors like to repeat the quote that “when the tide goes out, that’s when we find out who’s wearing no pants.” When Tesla actually weathers its first market downturn is when we find out how much investors interest is maintained When investment dollars are scarce.

      • Oh no! He promised my car would be self driving in 2018 but it took until 2026 before that was true.

        How dare he not have accurately predicted when one of the hardest technical problems in history is solved?

        • “At SpaceX we specialize in making the impossible merely late.” -Elon
    • Regarding 3, they're almost certainly thinking of putting these in SSO where the radiation environment isn't too much worse than you see on the ISS. If they were going to go outside the Van Allen belts it would be a different story.
    • The whole AI bubble makes way more sense if you model it not as rational economic activity, but rather as the actions of a rogue AI slowly taking over our institutions and redirecting them towards its goals. Data centers in space make no sense economically, but think of how survivable the rogue AI will be once we build those orbiting data centers! (I am joking about this, but it's weird that my logic makes sense.)
    • Added some math on my comment that outlines the boundaries of economics of this considering most of what you mentioned.
    • > 5. Energy production will be cheaper from earth

      Sun-synchronous orbit means solar panels collect the same amount 24/7. I guess that's the #1 benefit. Cheap energy.

      • Read the whole sentence. He’s talking about the cost to make solar panels that can be deployed in space, not the efficacy of said panels.
    • for the chips to both be radiation hardened and as powerful as our current chips they'd need to be massive. There's a reason the mars rover uses a PowerPC G3
    • It doesn't make sense. It is just Musk trying to pump up SpaceX valuation before the IPO.
    • >Ingress/egress are almost always a major bottleneck - how is bandwidth cheaper in space?

      Free space optics are much faster than data to/from the ground. If the training workloads only require high bandwidth between sats, this isn’t a real issue.

    • > Chips must be “Rad-hard” - that is do more error correcting from ionizing radiation - there were entire teams at NASA dedicated to special hardware for this.

      They don't do RAD hardening on chips these days, they just accept error and use redundant CPUs.

      • There are apparently rad-hard DDR4 chips these days so this is patently false. SpaceX used to talk a lot about substituting rad-hard components with triple redundant regular x86 years ago, that's true.

        I think I've also seen someone mention that the cost and power benefit of substituting rad-hard chips with garden variety wean off fast once the level of redundancy goes up, and also it can't handle deep space radiations that just kill Earthbound chips rather than partially glitching them.

      • You are confidently incorrect. Even Starlink uses rad-hardened CPUs. Redundant error correction is only really an option on launch hardware that only spends minutes in space.

        Note that on modern hardware cosmic rays permanently disable circuits, not mere bitflips.

        • > You are confidently incorrect.

          No, he's not. Dragon is using CotS, non rad-hardened CPUs. And it's rated to carry humans to space.

          > AWST: So, NASA does not require SpaceX to use radiation-hardened computer systems on the Dragon?

          John Muratore: No, as a matter of fact NASA doesn't require it on their own systems, either. I spent 30 years at NASA and in the Air Force doing this kind of work. My last job was chief engineer of the shuttle program at NASA, and before that as shuttle flight director. I managed flight programs and built the mission control center that we use there today.

          On the space station, some areas are using rad-hardened parts and other parts use COTS parts. Most of the control of the space station occurs through laptop computers which are not radiation hardened.

          > Q: So, these flight computers on Dragon – there are three on board, and that's for redundancy?

          A: There are actually six computers. They operate in pairs, so there are three computer units, each of which have two computers checking on each other. The reason we have three is when operating in proximity of ISS, we have to always have two computer strings voting on something on critical actions. We have three so we can tolerate a failure and still have two voting on each other. And that has nothing to do with radiation, that has to do with ensuring that we're safe when we're flying our vehicle in the proximity of the space station.

          I went into the lab earlier today, and we have 18 different processing units with computers in them. We have three main computers, but 18 units that have a computer of some kind, and all of them are triple computers – everything is three processors. So we have like 54 processors on the spacecraft. It's a highly distributed design and very fault-tolerant and very robust.

          [1] - https://aviationweek.com/dragons-radiation-tolerant-design

          • > Dragon is using CotS, non rad-hardened CPUs. And it's rated to carry humans to space.

            Those are not independent facts. They put the hardware inside, behind the radiation shielding they use to keep the astronauts safe. It's why regular old IBM laptops work on the Space Station too. That kind of shielding is going to blow your mass budget if you use it on these satellites.

            SpaceX, which prefers COTS components when it can use them, still went with AMD Versal chips for Starlink. Because that kind of high performance, small process node hardware doesn't last long in space otherwise (phone SoC-based cubesats in LEO never lasted more than a year, and often only a month or so).

            • > They put the hardware inside,

              Which is exactly how you'd do a hypothetical dc in space. Come on, you're arguing for the sake of arguing. CotS works. This is not an issue.

              > That kind of shielding is going to blow your mass budget

              SpX is already leading in upmass by a large margin. Starship improves mass to orbit. Again, this is a "solved" issue.

              There are other problems in building space DCs. Rad hardening is not one of them. AI training is so fault tolerant already that this was never an issue.

              • None of the discussed designs include radiation shielding like that. Nobody is considering doing it that way, because the math really really doesn’t work out (instead of unshielded, where it just doesn’t work out).

                A cosmic ray striking a chip doesn’t cause a bitflip - it blows out the whole compute unit and permanently disables it. It is more like a hand grenade going off.

              • > AI training is so fault tolerant already that this was never an issue.

                Such nonsense.

                • Between fp nondeterminism, fp arithmetic, async gradient updates, cuda nondeterminism, random network issues, random nodes failing and so on, bitflip is the last of your concerns. SGD is very robust on noise. That's why it works with such noisy data, pipelines, compute and so on. Come on! This thread is having people find the most weird hills to die on, while being completely off base.
          • Carrying humans to space is not the same use case as spending long periods of time in orbit.
            • Dragon spends 6mo+ in orbit regularly. I have no idea what's happening in this thread, but it seems everyone is going insane. People don't even know what they're talking about, but they keep on bringing bad arguments. I'm out.
      • Where did you hear this?
    • When they talk about "space" they are, right now, talking about the moon. Which has some gravity. They are putting the data centers on the moon. And the satellites are lunar satellites not earth-orbit satellites. Lonestar physical data center payload landed on the moon in Feb 2025 and Sidus space developing the lunar satellites.
      • They are not. xAI/SpaceX is talking about millions of satellites in sun-synchronous orbit.
        • Yeah, the cost of doing it on the moon would be even more astronomical. Then there also is the three second of round-trip latency to consider (ca. 2.6 s just the signal, but processing adds a bit more).
  • The really crazy thing is you don't need to know more then basic (non Hollywood) physics to know how dump this is

    1. every gram you need to send to space is costly, a issue you don't have at ground level

    2. cooling is a catastrophe, sure space is cold, but also a vacuum, so the cooling rate is roughly the infrared radiation rate. This means if you are not careful with the surface of a satellite it can end up being very slowly cooked by sunlight alone not including running any higher heat producing component (as it absorbs more heat from sunlight then it emits, there is a reason satellites are mostly white, silver or reflective gold in color). Sure better surface materials fix that, but not to a point where you would want to run any heavy compute on it.

    3. zero repair-ability, most long running satellites have a lot of redundancy. Also at least if you are bulk buying Nvidea GPGPUs on single digit Million Euro basis it's not rare that 30% have some level of defect. Not necessary "fully broken" but "performs less good then it should/compared to other units" kind of broken.

    4. radiation/solar wind protections are a huge problem. Heck even if you run things on earth it's a problem as long as your operations scale is large enough. In space things are magnitudes worse.

    5. every rocket lunch causes atmospheric damage, so does every satellite evaporating on re-entry. That wasn't that relevant in the past, but might become a problem just for keeping stuff like Starlink running. We don't need to make it worse by putting datacenters into space.

    6. Kessler Syndrom is real and could seriously hurt humanity as a whole, no reason to make it much more likely by putting things into space which don't need to go there.

    Last but not least, wtf would you even want to do it?

    There is zero benefit, non nada.

    • > sure space is cold

      Even this isn't true. It's ~120 degC in daylight in LEO. It only gets cold in the shade, but a solar powered data center is pretty useless in the shade.

      • The solar labels are in the sun. Behind them they are in the shade.
        • In close proximity, and connected to metal structures radiating & conducting heat at 120 degrees. You still have to expel that heat somehow, and route it around the spacecraft core.
          • I think stopping the heat conductivity is a solved problem - space telescopes manage to do this. But all in all, cooling in space remains a very big challenge.
            • No, it isn’t solved. The James Webb telescope was shipped with cryogenic coolant, and put in an orbit in the shadow of the moon far from the radiating earth. Once it runs out in a few years, it’s done.
        • The energy collected from the solar panels must be converted into heat in the AI chips. It's really like putting the AI chips directly into the sun, just with extra steps. Sunlight gets transformed into electricity which gets transformed into heat in the chips.
        • They actually need the entirety of the backside of the panels to cool them - if not they would literally burn out from the accumulated heat from being exposed to the sun.
    • The benefit is to siphon US tax money into billionaire pockets. It's insanely obvious and this has been Musk's MO for like 15 years now. Hyperloop? That was a grift to stop public transit from expanding. Tesla robo-taxis? Still waiting. FSD? Still waiting. Everything he does is a monumental grift to make himself richer and more powerful. The man is a hollow shell of a human being and the only thing that makes him feel anything is more money and power.
    • > The really crazy thing is you don't need to know more then basic (non Hollywood) physics to know how dump this is

      And yet journalists at major institutions have been repeating Musk's claims with very little skepticism ("xAI and SpaceX are merging to bring data centers to space").

      • I believe you're better served by editorials for opinion, journalism should be comparatively rigorous. "Musk says" is not "plans/hopes"
        • I can't tell what you're actually saying. Is "Musk says Moon is made of blue cheese" as a title, without pointing out the fact that the moon is not made of blue cheese a kind of "rigorous" reporting?

          Dealing in hallways gossip is not the job we granted the press extra constitutional protections for.

          • So, don't take this the wrong way, but basically: https://newsliteracy.wsj.com/news-opinion

            I was poorly trying to raise this trite distinction, asserting skepticism falls closer to Opinion than Journalism. The line gets more fine every day. I know. Take it up with them/their peers.

            'Rigorous' would be "Billionaire says '<crazy shit>'", not "Billionaire says '<crazy shit>'... and here's how we feel/think about it".

        • I'd argue this is not opinion but fact. Also, articles very often didn't say "Musk says" but just took his word for fact, not even quoting him. And in the era of Trump/Musk, their practices should evolve.
      • That sounds like what journalists usually do. They are reporters, and rarely have any real knowledge of what they report.
      • For people new to HN (Paul Graham - PG - is HN's founder):

        https://paulgraham.com/submarine.html

        > Why do the media keep running stories saying suits are back? Because PR firms tell them to. One of the most surprising things I discovered during my brief business career was the existence of the PR industry, lurking like a huge, quiet submarine beneath the news. Of the stories you read in traditional media that aren't about politics, crimes, or disasters, more than half probably come from PR firms.

        Musk is running out of runway on his way to infinity dollars and since Tesla is slowly crumbling compared to its valuation, the ideas need to become crazier and crazier: humanoid robots tomorrow, self driving taxis tomorrow, reusable rockets going to Mars tomorrow, data centers in space tomorrow.

        It would be fun to watch if Musk wouldn't funnel a lot of money that could be used for good, instead. Imagine how many diseases we could cure with all that money. Or feed and educate the poor. Or how much walkable and bikeable and ultimately liveable infrastructure we could build world wide. Or how fewer plastics we could use, ingest and discard if we could promote healthy and natural alternatives.

        And techies fall for his stories every time, hook, line and sinker, because he's speaking about core geek fantasies.

        • There is no accountability anymore. Literal crypto pump and dump schemes mint millionaires and funnel money to billionaires and not a single investigation, indictment, court case, sentence, or even fine!

          It's a casino and the mirage of billionaire competency would vanish instantly if the media were even slightly skeptical.

          The media is owned, it's a sham. It's a play.

          > And techies fall for his stories every time, hook, line and sinker, because he's speaking about core geek fantasies.

          Not all techies, but enough of them to keep the raft afloat.

      • The same thing happened with Hyperloop. Many journalists are simple stenographers of the utterances of others and there's no verification applied to any of the claims.
    • I don't know if data centers in space make sense or not, but I'm really not liking these comments that say something is "too expensive" or "too hard" without actually crunching the numbers to verify if it actually is. It's like you point out a number of completely obvious problems with the scheme and immediately, without any detailed analysis or expertise (I know this, because surely you can't have expertise in all of the problems you cited) in the said problems, claim that they are completely impossible for anyone to ever solve.

      > 1. every gram you need to send to space is costly, a issue you don't have at ground level

      This is a one time cost. Maybe the running costs are cheap enough to offset this.

      > 2. cooling is a catastrophe, sure space is cold, but also a vacuum, so the cooling rate is roughly the infrared radiation rate. This means if you are not careful with the surface of a satellite it can end up being very slowly cooked by sunlight alone not including running any higher heat producing component (as it absorbs more heat from sunlight then it emits, there is a reason satellites are mostly white, silver or reflective gold in color). Sure better surface materials fix that, but not to a point where you would want to run any heavy compute on it.

      I would assume the people designing this are "very careful" with everything they put in the data center. If achieving the cooling is only very hard and requires careful material engineering, then it can be worked out and they will get it done. If it is impossible, then this will not happen, but I'm a physicist myself and I can't tell without a very involved analysis whether it is impossible or not to get enough cooling power for this in space, considering all, possibly ingenious ways to engineer the surfaces of the data center to dissipate a maximum amount of heat.

      > 3. zero repair-ability, most long running satellites have a lot of redundancy. Also at least if you are bulk buying Nvidea GPGPUs on single digit Million Euro basis it's not rare that 30% have some level of defect. Not necessary "fully broken" but "performs less good then it should/compared to other units" kind of broken.

      I suppose they could make something like the International Space Station, which would get regular traffic back-and-forth exchanging and servicing hardware as needed.

      > 4. radiation/solar wind protections are a huge problem. Heck even if you run things on earth it's a problem as long as your operations scale is large enough. In space things are magnitudes worse.

      Again, it's not a question whether this is "problematic"; everything about putting data centers in space is. The question is whether, with huge amount of work and resources, they can engineer a solution to overcome this. If they can, it's again a one time cost for the data center that might be offset by the running costs of the facility.

      > 5. every rocket lunch causes atmospheric damage, so does every satellite evaporating on re-entry. That wasn't that relevant in the past, but might become a problem just for keeping stuff like Starlink running. We don't need to make it worse by putting datacenters into space.

      > 6. Kessler Syndrom is real and could seriously hurt humanity as a whole, no reason to make it much more likely by putting things into space which don't need to go there.

      These are collective problems for the whole of humanity and will not concern an individual actor such as Elon Musk who wants to send more satellites into space.

      • Yes, this is the nature of Brandolini's Law.

        > I would assume the people designing this are "very careful" with everything they put in the data center

        Which is very nice for Musk, who can spend 30 seconds running his mouth, and people jump to assuming that a) it's being designed, b) by skilled people, c) the math and finances works out already, d) that 'completely obvious' problems must simply be your lying eyes, and contort themselves to put all the effort into defending it.

        Even though Musk has a history of lying announcements and not being able to deliver and the 'completely obvious' problems were actually problems that nobody solved. Where is the 2017 full self driving car? Where is the Vision-over-LIDAR success? Where is the Hyperloop that "would be able to whisk passengers from L.A. to San Francisco in just 35 minutes"? Where are the 2025 orbital refuelling test flights for the Moon and Mars schedule, and the plans for how to keep cryogenic liquid Hydrogen cold in Space? Where was the "funding secured" Musk lied about for taking Tesla stock private in 2018 when judges found there wasn't any funding and fined him $20M? Where's the person Musk said in 2011 he could "put on Mars in a decade"? Where's the uncrewed Mars ship in 2022 he announced in 2017? The human voyage in 2024?

        > "I'm a physicist myself"

        And if someone tells you they have found a quantum zero-point free energy room temperature superconducting over-unity perpetual motion machine, do you jump to their defense because you assume the speaker must be very careful and smarter than everyone else? Or do you say "sounds unlikely; extraordinary claims require extraordinary evidence"?

        > "I suppose they could make something like the International Space Station, which would get regular traffic back-and-forth exchanging and servicing hardware as needed."

        The ISS cost 100-150 billion, is "larger than a 6 bedroom house", and its solar panels can generate 250 kW. NVidia says their AI datacenter costs $50-60 billion, needs 1GW of electricity, and look at the size of it: https://www.businessinsider.com/why-nvidia-worth-5-trillion-...

        You're looking at that multiple-warehouses-structure which could sink the output of an entire nuclear power station, and going with "it would be cheaper if we launched that into space"?

      • > This is a one time cost

        > which would get regular traffic back-and-forth

        I hope it's not a mystery why this commemt has been downvoted

      • > This is a one time cost.

        Sure, until you need to replace or upgrade it. How long does a server on earth last for, how often does it need maintenance / replacing? And how long is the expected or desired lifetime for a server in space? Then calculate weight and cost etc.

        > Maybe the running costs are cheap enough to offset this.

        "Maybe" is hope, you can't build a business on hope / wishful thinking. And the running costs for data centers on earth can be reduced too if you build them the same way as a sattelite - solar panels + battery + radiative cooling gives you enough data to compare. But servers / data centers aren't built that way because of cost vs benefit.

        > If achieving the cooling is only very hard and requires careful material engineering, then it can be worked out and they will get it done.

        See, it's possible for sure - we HAVE computers in space, powered, cooled, running 24/7. The questions are whether it makes economic sense, both launch costs and running / maintenance costs. That's straight math, and the math isn't mathing.

        > I suppose they could make something like the International Space Station, which would get regular traffic back-and-forth exchanging and servicing hardware as needed.

        Sure, but the ISS itself cost ~100 billion to build and operate - probably more, this is based on a ten second search query. While I'm sure launches are cheaper than ever and will be even cheaper in the future, it's still tens of billions to build a data center in space, plus you'd need astronauts, supplies, hardware, etc - all a LOT more expensive than the equivalent processing power on earth.

        > These are collective problems for the whole of humanity and will not concern an individual actor such as Elon Musk who wants to send more satellites into space.

        True, so we as humanity should offer resistance to plans to launch thousands of objects into space unless they have a clear and definite benefit. I'm not worried about Starlink, it's a benefit to all the areas that don't have (open) access to the internet and they're in low-earth orbit so they'll fall back within 5 years. But I just don't see the benefit in putting datacenters in space, not when it's so much cheaper and more viable to put them on earth.

  • I'm convinced that >30% of this comes from ideas leaking out of fiction such as like Neuromancer, and percolating through the minds of wealthy people attracted to some of the concepts. Namely, the dream of being a hyper-wealthy dynasty, above any earthly government, controlling an extraterritorial Las Vegas Fiefdom In Space. (Which in the book, also hosted a powerful AI.)

    Then they work backwards, trying to figure out some economic engine to make it happen. "Data centers" are (A) in-vogue for investment right now and (B) vaguely plausible, at least compared to having a space-casino.

    • That's not fair! Sometimes the ideas come from Snow Crash, which gave us the Metaverse because Zuckerberg wanted to cut a guy in half with a katana from a motorcycle.
      • Wait is that why they didn't put legs on anyone?
        • Wow, now you say it, that finally makes sense. Especially given it looked stupid and all the other VR chat solutions could already do legs.
        • I always assumed they were copying the Wii Miis
      • It also gave us Mechanical Turk and microdrones!
    • Some of it might come from True Names by Vernor Vinge too, where the cheapest place to buy bulk compute is giant satellites orbiting on geosync orbit. This became possible because they were developed early on for communications, then obsoleted by Starlink-like LEO constellations, so they have a ton of spare undesirable high-latency capacity to sell. In this fictional world, ground-based fiber optic networks never happened, at least not at the kind of scale they did in the real world.

      But because that's fiction, Vinge can just handwave away all the hard engineering problems for sci-fi flavor.

    • “And, for an instant, she stared directly into those soft blue eyes and knew, with an instinctive mammalian certainty, that the exceedingly rich were no longer even remotely human.” ― William Gibson, Count Zero
    • This idea came from musk wanting to fold his X and xAI investments in with his (likely successful) spaceX IPO.
      • Yup, likewise Starlink - while space internet is an interesting and viable concept (whether it'll earn itself back is another question, I'm not convinced), the real motivation behind it was to create demand for many SpaceX launches. There have been 352 Starlink launches [0] so far, out of 596 total [1]. If it wasn't for Starlink, SpaceX would only have been operating at 1/3 to 1/2 of what it does today, cutting into their "economics of scale". And they'll need demand to make Starship viable, the possible moon missions aren't enough to fund or justify the whole project. Hence also the ideas of colonising Mars, which - if someone is willing to pay for it - would create a large and steady demand for launches / flights.

        [0] https://en.wikipedia.org/wiki/List_of_Starlink_and_Starshiel...

        [1] https://en.wikipedia.org/wiki/List_of_Falcon_9_and_Falcon_He...

      • Yeah, if he gets more SpaceX shares in exchange for the xAI garbage shares then he wins, because the SpaceX shares will sell well.
        • He can also hide his garbage shares behind a too big to fail, essential for national security, business.
        • Also he can launder government funding for his AI company now
    • I am surprised the space casino hasn't been done to be honest. Or some kind of space resort. I guess we are stepping across the stepping stones now, with private space flights, and private space fairing companies. Maybe it is just a matter of time before the Crystal Palace sees its first billionare clients.
      • > I am surprised the space casino hasn't been done to be honest. Or some kind of space resort.

        The ISS is the single most expensive thing built by humankind ($100b+). What makes you think that building a "space casino" or "space resort" is commercially viable?

    • I wouldn’t credit science fiction for much of this.

      It appears to have come out of a crack pipe.

    • I’ve come to think of interviews with people like Sam Altman as “freestyle science fiction.” They’re just saying stuff off the top of their head. Like you say, that often entails vague ideas from other sci fi percolating up and out, with no consideration of if they actually make sense. And like most freestyle, it’s usually pretty bad.
      • That is possible because DOGE and their comrades gutted the SEC and indirectly FINRA like a fish. The government is run by confidence men running crypto scams.

        That’s how the CFO of OpenAI can essentially say “we need a Federal bailout”, and then turn around and say “lol just joking”.

        • [checks today's bitcoin price]

          Oh.

          Is it below the level where mining and blockchain updates become uneconomic yet?

      • I'd say they're basically floating on the success of previous sci-fi ideas that they made a reality; reusable rockets at a fraction of the price of NASA or ESA launches for example, or self-driving electric cars (the electric part was a success, the self-driving, not so much).
      • Your dad can’t tell the difference.

        If they get 3/10 things right, and 60 Minutes highlights those in the next interview, they’re set!

    • > above any earthly government

      Anti satellite weapons are a thing. Besides, the more vulnerable part becomes you as a person rather than the equipment. There's no space colony yet, and even if there is, the supplies can be easily held hostage by an earthly government too.

    • He is very influenced by The Culture of Iain Banks. They're really good sci-fi... and describe a hedonistic world where machines do the hard thinking and bidding of the biologicals.

      https://recommentions.com/elon-musk/books/culture-by-iain-ba...

      https://www.vox.com/culture/413502/iain-banks-culture-series...

      https://fortune.com/2025/12/15/billionaire-elon-musk-say-tha...

      > Musk pointed to The Culture series by Iain M. Banks as his best “imagining” of this world. The science fiction novels depict a utopian future where citizens can have virtually anything they want thanks to AI—making money obsolete and leaving citizens free to spend their time doing whatever they love.

    • I mean definitely, and they're not shy about admitting it. They see cool stuff in imagination-land, think it's cool, and work to make it a reality. Many people have worked to make the fantastical things shown in Star Trek.
      • We're about as close as we have ever been to a holo-deck with VR/AR right now, but it is notable that it is still a fringe technology. I think basically no one cares about space data centres except the rule of cool enthusiasts in the technosphere.
        • The harsh reality of economics and demand is hitting them. For years, Musk's ideas were funded by an overvalued Tesla stock and stupendous amounts of investor money, and currently it's being double down on with the amount of money being poured into AI and its necessary hardware.

          But the demand / economic viability just isn't there. VR is cool but it's not mainstream. "Metaverse" exists and some companies are making good money off of it (Roblox, Fortnite, MMOs, etc), but nobody wanted Facebook's multi-billion-dollar-invested version of it because they just don't get it. I really hope all this nonsense collapses sooner rather than later and we go back to realistic and viable spending.

          Large investments don't translate to results.

    • well, don't forget, freeside's initial moneymaker was a datahaven for less-reputable banks!
    • A lot more. Everyone is chasing scifi ideas, ridiculous. This shows that even people with high IQ lack fantasy/imagination and creativity. They are intelligent robots.

      So whenever I see here or anywhere else that your ideas mean nothing I just laugh at it. Of course, these come from people who are bland, doesn't have any imagination and they are not creative at all at all, but they have brute force, which is money.

      • Write some books with good ideas then so future human-robots will be inspired to make your dreams into reality.
        • Unfortunately, these guys are only excited about building the Torment Nexus.
          • From the classic sci-fi novel "Do Not Create The Torment Nexus".
          • "It's only Torment™ if you aren't a double-digit shareholder!"
    • Stole Grok from Heinlein. At least it’s a good heuristic for people-I-don’t-have-to-take-seriously.
      • More likely, stole grok from nerds who learned grok from Heinlein.
      • Heinlein's sci fi didn't age well, because it was written for juveniles and then later his social ideas overtook his sci fi ones.

        He had the same blind spots that Ayn Rand did, but perhaps better informed of the fascist-adjacent US culture.

        One of the good sci fi/social ideas he had was about what it meant to "grok" something. groklaw.net of happy memory was exactly what that verb was supposed to mean, dive into something until you understand it at a molecular level.

        The fact that Musk et al have stolen terms like "grok" and even "cyberspace" as if they own them is something I loathe.

  • benl
    Data centers in space may or may not make sense (personally I'm quite skeptical) but the objections in the article certainly don't make sense.

    1. The only reason there are 15,000 satellites in space is because SpaceX launched about 9,500 of them (Starlink is 65% of all satellites) on their semi-reusable Falcon 9. If fully-reusable Starship pans out, they will be launching satellites at 10x the rate of Falcon 9 at the very least.

    2. You don't need to upgrade the satellites, you just launch new ones. The reason data center companies upgrade their servers is because they can't just build a new data center to hold the new chips. But satellites in space are a sunk cost, so just keep using the existing satellites while also launching new ones.

    3. Falling solar panel costs decreases the power costs for both earth-based and space-based, but they're more efficient in space so the benefit would be proportionally greater there.

    As I said, I'm skeptical too, but let's be skeptical for good reasons.

    • A few additional items to rebut the lack of info in this Article:

      - SpaceX just requested a license to launch up to a million satellites.

      - the satellites already have some incredible anti collision software, which I believe Elon has now open sourced.

      - the cost to launch 1 kg to space has dropped by a factor of 10 in the past few years and is currently less than $1000. It's perfectly reasonable to estimate that over the next 10 years the cost could drop by another factor of 10, if not more, particularly if the heavy rockets are reusable.

      1. https://techcrunch.com/2026/01/31/spacex-seeks-federal-appro...

      2. https://starlink.com/updates/stargaze

      3. https://www.netizen.page/2025/05/cost-per-kilogram-to-low-ea...

      Edit: added item 3

      • Elon has open sourced them, or the people at SpaceX who actually know or understand something did?
        • Open sourcing your company's secret sauce is probably the sort of decision that only the CEO approves.
    • 3. The falling costs won’t benefit space as much. The cost of sending mass to space will still be a big factor in the space solar panel costs. Much of the reason why solar is getting cheaper is not the panels themselves, but due to innovations that reduce installation costs. Those don’t apply to space (outside of the already assumed reductions in sending mass to space to make this viable)
      • Yes, launch cost is the crux of the matter. My skepticism is based on whether they’ll be able to get launch cost low enough and launch cadence high enough. SpaceX has shown the ability to get launch costs dramatically lower and cadence dramatically higher, but it’s not a slam dunk that those curves will continue to the levels needed for this idea to work.
    • 2) it is extremely common to add storage to existing servers. Only slightly less; RAM, CPUs etc. not to mention how often it is cost-effective to replace broken components.
  • Data Centers in space make no sense due to radiation.

    You cannot do two things at the same time:

    1. Make electronics small. 2. Make electronics radiation resistant.

    It’s a numbers game. The denser things are packed, the higher the probability that a random high energy particle or ray will damage something.

    20 years ago NASA was buying old chips, because those were less susceptible, modern “radiation hardened by design” chips are better than those, but still slower than those for planetary use.

  • The crux of it is that radiative cooling in space is dependent on exposed surface, not total surface area like a radiator or heatsink on earth - this means if you just put an existing finned heatsink in space it would radiate most of it's heat back to itself - the only net cooling you'd have is the amount that can radiate outwards without hitting itself.

    For a benchmark - the IIS uses about 4500sqft (420 sqm) of radiators just to keep it's onboard equipment (~70KW) cooled. That's ~150-200 W/sqm.

    That means, per GPU, you'd need about 2.5-3.0 sqm of passive radiators.

    For a 1MW satellite (~8 datacenter racks of GB200/NVL72) you'd need basically half a football field of bleeding-edge solar panels (that also need to radiate their heat on the reverse side) and a similar sized cooling array of heat radiators for the electronics.

    This is on the scale of 40-50 tons - about 10% of the IIS. This should fit on falcon heavy or starship - assuming the solar array and radiators can fold up to fit inside. You could, purely based on weight, launch 2 of these per starship launch.

    If you consider the Opex savings (electricity, rent, facilities maintenance) and putting 2 of these on a single starship launch, I still think the ROI would be too long. You're saving about ~$1M per year in Opex but it's costing you $25M to launch it into space and likely an extra ~$50M in satellite equipment (based on starlink satellite costs) on top of the compute. Will those GPUs still be useful in 10 years? Probably not.

    I don't think the math is there that justifies the free electricity - even at gigawatt scale (thousands of satellites mass-produced) and at a dramatically lower cost per satellite and per launch. Getting costs down on this would involve tightly integrating the compute and the satellite hardware which would make upgrading the compute independently from the cooling/power infrastructure in the future a significant challenge.

    • The lifetime of a GPU in practice is around 3 years. There is no way this plan is going to work. Musk knows that, he's just counting on stupid people to buy into the SpaceX IPO on hype.
    • Makes me wonder:

      Back in the early 1990s I read some children's futurist book that suggested that we might send solar panels to space that would then beam energy via microwaves to the surface. The book was more fantasy than science, so I took it with a huge grain of salt and appreciated it for its entertainment value.

      But do you think schemes that try to direct solar energy to the surface are more practical then running datacenters in space?

      • Space based power arrays with microwave transmission to massive ground fields has been discussed for nearly sixty years. It doesn't make economic sense, at all.

        https://caseyhandmer.wordpress.com/2019/08/20/space-based-so...

        I would love it to be a thing, but it is not a thing.

      • I don't think there is calculus that makes the cost of getting it to space worth putting it there - Elon of all people knows this - if you scale up the ground-based solar and add battery storage, the costs are still far lower than trying to put that in space to gain more hours of usable sun and higher intensity sun... it's just not cost effective until panels are paper thin, weigh nothing and the cost of launches and thus per-ton to orbit gets an order of magnitude cheaper.
  • As the focus here is solely on the US, and the comments focus too much on the impossibility of heat dissipation, I want to include some information to broaden the perspective.

    - In the EU, the ASCEND study conducted in 2024 by Thales Alenia Space found that data center in space could be possible by 2035. Data center in space could contribute to the EU's Net-Zero goal by 2050 [1]

    - heat dissipation could be greatly enhanced with micro droplet technology, and thereby reducing the required radiator surface area by the factor of 5-10

    - data center in space could provide advantages for processing space data, instead of sending them all to earth. - the Lonestar project proved that data storage and edge processing in space (moon, cislunar) is possible.

    - A hybrid architecture could dramatically change the heat budget: + optical connections reduce heat + photonic chips (Lightmatter and Q.ANT) + processing-in-memory might reduce energy requirement by 10-50 times

    I think the hybrid architecture could provide decisive advantages, especially when designed for AI inference workloads,

    [1] https://ascend-horizon.eu/

    • > Data center in space could contribute to the EU's Net-Zero goal by 2050

      How unbelievably crass. "Let's build something out of immense quantities of environmentally-destructive-to-extract materials and shoot it into space on top of gargantuan amounts of heat and greenhouse gas emissions; since it won't use much earth-sourced energy once it's up there, that nets out to a win!"

      Insane.

      • Blue Origin at least runs its rockets on hydrogen whose exhaust is only water.
        • And heat and pressure. Negligible amounts in terms of the biosphere, but not in terms of flora and fauna in proximity to launch sites.
        • Where do they get the hydrogen without putting a load of CO2 into the atmosphere just to manufacture the hydrogen to begin with?

          One thing to think about is debt which is not in terms of money.

          People are becoming more familiar with "technical debt" since otherwise it comes due by surprise.

          With hamsterwheels in space you've got energy debt.

          Separate from all other forms of debt that are involved.

          Like financial debt, which is only a problem if you can't really afford to do the project so you have to beg, borrow, and/or steal to get it going.

          On that point I think I'd be a little skeptical if the richest known person can't actually afford this easily. Especially if he really wants it with all his heart, and has put in any worthwhile effort so far.

          Anyway, solar cells are kind of weak when you think about it, they don't produce the high output of a suitable chemical reaction, like the kind that launches the rockets themselves. Which releases so much energy so fast that it's always going to take a serious amount of time for the "little" solar cells to have finally produced an equal amount of energy before a net positive can begin to accrue.

          Keeping the assets safely on the home planet simply provides a jump-start that can not be matched.

          All other things being unequal or not.

    • > micro droplet technology

      Intentionally causing Kessler Syndrome?

      > A hybrid architecture could dramatically change the heat budget: + optical connections reduce heat + photonic chips (Lightmatter and Q.ANT) + processing-in-memory might reduce energy requirement by 10-50 times

      It would also make ground-based computation more efficient by the same amount. That does nothing to make space datacenters make sense.

      • Kessler syndrome is only a problem if the satellites are in LEO. They don't have to be.
        • They do have to be if they want to be approved by the FCC.

          And btw Kessler syndrome applies to any orbital band. You've got the logic backwards. Kessler syndrome is usually only considered a threat for LEO because that's where most of the satellites are. But if you're throwing million(s) of satellites into orbit, it becomes an issue at whatever orbital height you pick.

    • > reduce energy requirement by 10-50 times

      This is only relevant to the compute productivity (how much useful work it can produce), but it's irrelevant to the heat dissipation problem. The energy income is fundamentally limited by the solar facing area (x 1361 W/m^2). So the energy output cannot exceed it, regardless useful signals or just waste heat. Even if we just put a stone there, the equilibrium temperature wouldn't be any better or worse.

  • As long as we're pointing out things that don't make sense: A long time ago in the United States we decided to run electricity _everywhere_, even farmhouses in the middle of nowhere. The solution to broadband in the United States is somehow, inexplicably "Let's use satellites" rather than increase tower coverage or run hard lines. It is a _terrible_ solution to this problem based on the cost alone.
    • I've used Starlink and it's fantastic in rural areas. Why dig thousands of miles of holes for physical wires when the problem is already solved?
      • Think. You don't even need to dig. We have myriad wireless internet solutions. We did not need to send satellites into space to fix this problem in a far more cost effective way.
        • Terrestrial wireless internet solutions are stupid. With a satellite you can be anywhere with line of sight to the southern sky and receive signal. With some shitty tower you're still constrained to your location just as you would be with wired, except that instead of a fast, low latency cable you have a noisy, outage prone wireless tower.
          • This is not a problem that needed to be solved by satellites. It is a failure of US politics that rural areas don't have broadband. We didn't need some private company to put satellites into low earth orbit for someone to watch a youtube video from their house reliably. The ongoing costs and complexities of running a global satellite network vs running a cable is insane.
  • The bull case IMO is that you can just produce very standardized ai satellites, load them into Starship, blast them off and have them work. And that the cost of that versus permitting etc will be less than trying to do it on land. I kind of believe it could get there. We could build nuclear reactors next to giant facilities but...we can't really seem to do it in the US? China seems to be able to do it.

    PS. I think the authors argument that millions of satellites might run into each other is silly. There are like 1.5 B cars.

  • Very confused by this plan. Data centers on Earth are struggling with how to get rid of waste heat. It's really, really hard to get rid of waste heat in space. That seems to be about the worst possible place to put a data center.
    • It’s a distraction as they suck out as much value from Tesla as possible before the music stops and they go bust. There are a few really big IPOs this year including SpaceX, which will likely trigger significant market volatility.
      • 93po
        yes, tesla, famously the worst performing car manufacturer with the worst profit margins, is definitely going bust any day now
        • Here's some context: Tesla, BYD, and Xiaomi Are Playing Different Games https://gilpignol.substack.com/p/tesla-byd-and-xiaomi-are-pl...
        • Clearly 200 forward P/E and three consecutive quarters of missed earning is a sign of profitability.

          It's a stock worth $50-60 with generous valuation. The premium is the Elon bullshit and grift. That isn't gonna last forever.

        • > Sales of Tesla's electric Cybertruck fell 48% in 2025, new data shows.

          > Tesla sold 20,237 Cybertrucks in 2025, down from 38,965 the previous year, according to figures from Kelley Blue Book's annual electric vehicle (EV) sales reports.

          https://www.cbsnews.com/news/tesla-cybertruck-sales-elon-mus...

          > A federal safety report shows that Tesla is recalling 63,619 of its futuristic pickups, and this seems to be the total number of Cybertrucks built since the first one was delivered at the end of 2023.

          https://www.arenaev.com/teslas_latest_recall_reveals_real_cy...

          > Musk said that it's time to put the Model S and Model X vehicles to rest. Now it's not that huge of a change, given that 97% of Tesla's sales consist of Model 3 and Model Y cars, but the Model S is still the original car delivered by Tesla.

          https://www.arenaev.com/tesla_discontinues_the_model_s_and_m...

          > The financial report paints a grim picture for the company. Tesla's total profit for 2025 was €3.24 billion. That is a lot of money, whichever way you look at it, but it is actually 46 percent less than what the company made in 2024. The profit margin, which is the percentage of money the company keeps after paying expenses, fell to just 4.9 percent. In 2022, that number sat at 23.8 percent.

          > One of the most interesting parts of the financial report is how Tesla made its money. A large chunk of its profit did not come from selling EVs to people. Instead, it came from selling "regulatory credits" to other car companies that need help meeting pollution rules. These credits brought in €2 billion.

          > That means 52 percent of Tesla's entire profit for the year came from these credits, not from selling vehicles. If Tesla did not have those credits, the financial results would look much worse. And the problem the company is facing? Those credits are gone; they won't be part of Tesla's business model this year since they were cancelled by the current administration.

          https://www.arenaev.com/tesla_profits_drop_as_automaker_star...

          Tesla is betting on long shots like humanoid robots and self driving taxis everywhere. There are other desperation moves like merging Tesla (profitable) with SpaceX (I think it's also profitable? but most of its business is governments: risky markets) and xAI (most likely wildly unprofitable, just like Twitter).

        • Keep up.
        • > with the worst profit margins

          The 2025 profit margin for Telsa was 4.6%. Toyota's was 9.4%. Telsa is famously on a multi-year sales and revenue decline.

    • That's not Elon's problem. He's an ideas guy. Data centers in space is definitely an idea.
      • Indeed. I would go so far as to assert that, of all the ideas that have ever been proposed in the history of humanity, data centres in space is most certainly one of them.
        • Just ask this scientician.
          • Uhhhh
            • >data centres in space is most certainly one of them.

              >Uhhhh

              Thanks, I wouldn't have noticed how wrong that was otherwise ;)

              It's most certainly two of them.

      • Yeah he only micromanages (look at his old blog) every detail he has time for at an extremely successful aerospace engineering company, just an ideas guy.
        • > Yeah he only micromanages (look at his old blog) every detail he has time for at an extremely successful aerospace engineering company, just an ideas guy.

          Have you ever spoken to someone who works at SpaceX? I have multiple friends in the industry, who have taken a trip through the company.

          The overwhelming consensus is that - in meetings, you nod along and tell Elon "great idea". Immediately after you get back to real engineering and design things such that they make sense.

          The folks working there are under no delusion that he has any business being involved in rocket science, it's fascinating that the general public doesn't see it that way.

          • Any cool kid in uni has had the same views as you do for ten years.

            What do you and them know that the countless extremely successful engineers who actually worked with Elon do not?

            https://erik-engheim.medium.com/is-elon-musk-just-a-sales-gu...

            • > What do you and them know that the countless extremely successful engineers who actually worked with Elon do not?

              Did you read my comment?

              "I have multiple friends in the industry, who have taken a trip through the company."

              I am literally referring to extremely successful engineers who have worked directly with Elon.

              I'm going to need more than a puff piece on some random Elon stan's medium page to outweigh what I've heard from my friends.

              • [flagged]
                • > This medium page simply quotes people. Feel free to quote your imaginary friends on your own medium page.

                  Simply quotes people with obvious large financial interest in the success of the company, who are therefore motivated to continue the super genius narrative.

                  I guess we all have our biases - I believe first hand accounts, you believe social media posts. To each his own.

          • Or you are actively trying to have the meetings when you are sure he cannot be present because he keeps derailing them.
          • Why are they doing any better than any other firm then? Why has Tesla been successful? Why is xAI pretty similar in terms of approach? My idea has less variables than yours. It also doesn't fly with his tendency to fire people.
            • > Why are they doing any better than any other firm then?

              Any other firm, you mean like the bloated and bureaucratic NASA/JPL/defense contractor madhouse? That's not much competition.

              > Why has Tesla been successful? Why is xAI pretty similar in terms of approach? My idea has less variables than yours. It also doesn't fly with his tendency to fire people.

              Your "idea" (statement) is that his companies are successful due to his micromanagement. In reality, they're successful in spite of it. Like all impactful engineering institutions, there are incredibly talented people working at the "bottom" levels of these companies that hold the whole thing together.

              There's a good bit of irony here in your thought that he'd fire people that didn't agree with him or disobeyed him. From what I've heard, he lacks the technical rigor to even understand how what was implemented differs from his totally awesome and cool, off the cuff, reality adjacent ideas.

              The myth of the supergenius CEO has real potential to influence investors, beyond that, the hard engineering is up to the engineers. Period. SpaceX wouldn't have gotten past o-ring selection with Elon at the engineering helm.

              • > NASA/JPL/defense contractor

                Perhaps learn to look around the world. Europe has nothing, China is working on copying. New Zealand has RocketLab but looks like they've sold out to the states and is only for small payloads yet.

                • > Perhaps learn to look around the world. Europe has nothing, China is working on copying. New Zealand has RocketLab but looks like they've sold out to the states and is only for small payloads yet.

                  And which of those is also an American institution, with American educated employees and American cultural values, operating in an American legal and business framework?

                  Pretending NZ is a relevant comparison point is laughable. I bet SpaceX is also doing better than the 5th grade STEM class down the street!

                  Russia would've been a much better comparison given the history of the world we live in, but still not apples to apples.

            • Shedding the very slow process of “legacy” defense/aerospace companies, taking more risks, moving faster, accepting some setbacks etc does not mean you need to go full Musk. There is a middle ground.
            • Have you ever worked at a company? Was how profitable the company was directly related to how high-functioning it was? Not in my experience.
              • This is so true.

                When you boil it down though, sometimes more than one company is built using almost the same exact mold, and the only major difference between them is the idea that the business plan is bult around.

                More profitable ideas are good to have.

                High-functioning or not.

            • > Why has Tesla been successful?

              Survivor bias. He's had how many failed businesses? 10? Probably more.

            • The same reason why Microsoft was able to kick everybody else out of the PC operating system and office software sectors: everybody else was even less competent.
              • I always felt that Microsoft's winning move was to be consistently mediocre. They just waited until competitors screwed up. Now they're following in IBMs or Intel's footsteps - concentrating everything on the enterprise market and slowly dying.
              • Bill Gates was also pretty good
                • More capable at programming or kicking people out of contention?
          • I have heard similar things
    • Very confused by this plan.

      How about now? https://www.bbc.com/news/articles/ce3ex92557jo

      • Well this explains why, but does not answer how to get rid of excessive heat in space.
        • What kind of the problem you're talking about compared to existing satellites? That is, all existing satellites generate power, and need to dissipate that power, and most of it goes to waste heat, and the satellites somehow do that successfully - what is the specific problem you're talking about, which can't be solved by the same means?
          • The numbers matter. The thermal budget a satellite is an tightly controlled thing. Large modern ones are in the order of a few to a couple of 10s of kilowatts, so something like a few to several low 10s of modern GPU compute power. Even with thousands of yet to be designed or launched satellites, it's going to have trouble competing with even a single current DC, plus it is in SAPCE for some reason, so everything is more expensive for lots of reasons.
            • > it's going to have trouble competing with even a single current DC

              This looks like a valid argument to me, yes. Elon mentioned 1,000,000 satellites - I'm thinking about 3rd version of Starlink as a typical example, 2 tons, 60 satellites per Starship launch, 16,000 Starship launches for the constellation, comparing with 160 launches per year of today's Falcon 9...

              The argument about problems of dissipating heat still stands - I don't see a valid counterargument here. Also "SAPCE" problem looks different from the point of view of this project - https://www.50dollarsat.info/ . Basically, out launch costs go way down, and quality of electronics and related tech today on Earth is high enough to work on LEO.

          • Even the buses for giant communications satellites are still at the single digit kilowatt scale. The current state of the art in AI datacenters is 500+ kw per rack.

            So you're talking about an entirely different scale of power and needed cooling.

          • The ISS's radiators weigh thousands of kilograms to radiate around 70 KW. He's talking about building data centers in space in the GW range.

            Assuming he built this in LEO (which doesn't make sense because of atmospheric drag), and the highest estimates for what starship could one day deliver to LEO (200 metric tons), and only 1 metric ton of radiators per 100KW, that's 50 launches just to carry up the radiators.

          • Are there many of those current satellites running gpus and actually generating lots of heat?
            • Principally speaking, as much energy as satellite receives from solar panels it needs to send away - and often a lot of it is in the form of heat. So, the question is, how much energy is received in the first place. We currently have some quarter of megawatt of solar panels of ISS, so in principal - in principal - we know how to do this kind of scale per satellite. In practice we perhaps will have more smaller satellites which together aggregate the compute to the necessary lever and power to the corresponding level.
              • > We currently have some quarter of megawatt of solar panels of ISS

                It's average outbut is like half of that though. So something the size of the space station, a massive thing which is largely solar panels and radiators, can do like 120kW sustained. Like 1-2 racks of GPUs, assuming you used the entire power budget on GPUs.

                And we're going to build and launch millions of these.

          • I mean you have this around the wrong way.

            The reason we dont have a lot of compute in space, is because of the heat issue. We could have greater routing density on communication satellites, if we could dissipate more heat. If Starlink had solved this issue they would have like triple the capacity and could just drop everything back to the US (like their fans think they do) rather than trying to minimise the number of satellites traffic passes through before exiting back to a ground station usually in the same country as the source. In fact, conspiratorially, I think thats the problem he wants to solve. Because wet dreams of an unhindered, unregulated, space internet are completely unanswered in the engineering of Starlink.

            I have actually argued this from the other side, and I reckon space data centres are sort of feasible in a thought experimental sense. I think its a solvable problem eventually. But heat is the major limiting factor and back of the napkin math stinks tbh.

            IIRC the size/weight of the satellite is going to get geometrically larger as you increase the compute size due to the size of the required cooling system. Then we get into a big argument about how you bring the heat from the component to the cooling system. I think oil, but its heavy again, and several space engineering types want to slap me in the face for suggesting it. Some rube goldberg copper heatpipe network through atmosphere system seems to be preferred.

            I feel like, best case, its a Tesla situation, he clears the legislative roadblocks and solves some critical engineering problem by throwing money at it, and then other, better people step in to actually do it. Also triple the time he says it will take to solve the problem.

            And then, ultimately, as parts fail theres diminishing returns on the satellite. And you dont even get to take the old hardware to the secondary market, it gets dropped in the ocean or burnt up on reentry.

        • It’s a vacuum
          • Vacuum being so famous for not conducting heat that we use it to keep our coffee hot
            • which is why the whole idea of data centers in space is ridiculous.
              • I'm glad to realize we're in violent agreement, I thought you were implying cooling would be easy due to the vacuum!
                • It can be solved with radiator fins and cold plates but yeah, it’s not an easy task.
    • You are confusing engineering challenges with show stoppers. Cooling in space is a well studied problem with a few possible solutions. They all boil down to needing a lot of mass to radiate heat out to the universe and ways to conduct heat. We've been doing that at small scale for decades. SpaceX is already operating a fleet of many thousands of satellites that they built and engineered. They'd be well familiar with this challenge.

      Once you have solutions, it turns into a cost problem. And if that cost is too high (for whatever arbitrary threshold you use for that) it becomes an optimization problem.

      This whole thread reads like a lot of "but ... but ... but ...". It all boils down to people assuming things about what is too much or too hard. And it's all meaningless unless you actually bother to articulate those assumptions. What exactly is too hard here? What would it take to address those issues? What would the cost be? Put some numbers on it. There are also all sorts of assumptions about what is valuable and what isn't. You can't say something is too hard or too costly without making assertions about what is worth paying for and what isn't.

      The answers are going to be boring. We need X amounts of giga tons launched to orbit at Y amount of dollars. OK great. What happens if launch cost drops by 1 or 2 orders of magnitude? What happens if the amount of mass needed drops because of some engineering innovation? Massively dropping launch cost is roughly what SpaceX is proposing to do with Star Ship. Is it still "too hard"? You can't have that debate until you put numbers on your assertions.

      There's a bit of back of the envelope math involved here but we're roughly talking about a million satellites. In the order of ~2.5 million tonnes of mass (at 2.5 ton per satellite). Tens of thousands of Star Ship launches basically. It's definitely a big project. We're talking about 1-2 order magnitude increase of the scale of operations for SpaceX going from lower hundreds to thousands of launches per year spread over maybe 10-15 years to work up to a million satellites.

      I'm more worried about what all that mass is going to do when it burns up in the atmosphere / drops in the oceans. At that scale it's no longer just a drop in the ocean.

      • Nobody is saying that building a data center in space is impossible. It's merely expensive.

        Who is going to pay the money to rent capacity in space when they could rent the same capacity on Earth for a fraction of the cost?

      • You make some good points, but when there are cheaper alternatives, engineering problems ARE showstoppers, and for good reason! If Musk announced that he wanted to build a datacenter inside an active volcano, my response would be pretty much the same - "Why?"
    • Well the issue is that a lot of people believe that space is cold. If you will ask Google/Gemini what is a temperature of space, it will tell you:

      The average temperature of deep space is approximately -270.45°C or 2.73 Kelvin), which is just above absolute zero. This baseline temperature is set by the Cosmic Microwave Background (CMB) radiatio...

      Which is absolute nonsense, because vacuum has no temperature.

      • Vacuum does have a temperature; it has a blackbody temperature.

        https://en.wikipedia.org/wiki/Black-body_radiation

        It has nothing to do with the movements of atoms, but just with the spectrum of photons moving through it. It means that eventually, any object left in space will reach that temperature. But it will not necessarily do it quickly, which is what you need if you're trying to cool something that is emitting heat.

      • That's not how it works. Two bodies are in thermal equilibrium if there's no heat transfer between them: that's the zeroth law of thermodynamics. If you're colder than 2.73K in deep space, you will absorb the heat from the Cosmic Microwave Background. If you're hotter, you will irradiate heat away. So it does have a temperature.
        • Does this mean that if Earth stays a fixed distance from the sun then its equilibrium temperature is fixed? I remember people saying things like that the albedo of the ice caps affected the Earth's temperature.
      • Well it isn't a perfect vacuum and it does have a temperature. But temperature is only a part of the story, just like how you go hypothermic a lot faster in 50 degree water than in 50 degree air.
      • I saw a news personality say that space is cold and that solves a big problem with datacenters as justification for why it made sense.
        • Space is cold because there isn't anything there.

          There is also no matter to wick the heat away.

      • but if you did use thermometer in space it would eventual read 2.73 kelvin right? so whats the issue? and also for a space based server it would have to deal with the energy coming from the sun
        • There is no matter.

          It's cold there because there isn't anything there.

          So there is nothing to conduct or convect the heat away.

          It's like a giant vacuum insulated thermos.

          Is putting data centers in thermos' a good idea?

          • i am not saying its a good idea, just wondering because you say space has no temperature, but that makes no sense for the reason CMB radiation would prevent you from having 0 k right? and in fact how would you even measure it? wouldn't the measuring device its self have way more then 0K?

            plus you would have to insulate the servers from the sun...then have radiators like the ISS... i think its just way easier to run a server on the ground

            • Why did you say "eventually" in your original post? That answers your question.
            • It's a rate problem
        • Yes and no.

          If you had a thermometer that had no heat generation then yes.

          If you have a resistor or other heat generating circuit then you need to have the needed surface area to radiate the heat away. If you don't, it will heat up. It's a rate problem.

        • what thermometer would you use to measure the temperature of space?
      • I'm not a scientist but i am also sure it will be fucking hard to dissipate heat in a vacuum
  • jtrn
    This sentence proves the author has no ability for logical thinking: Data centers in space only make sense if they are cost effective relative to normal data centers.

    I too don't think it's currently a sensible solution. But the author completely unable to make a proper case. For instance, just to refute that one claim, there are many reasons to do it in space even at an cost.

    Space-based data centers provide an off-world backup that is immune to Earth-specific disasters like earthquakes, floods, fires, or grid collapses. Servers in orbit are physically isolated from terrestrial threats, making them safe from riots, local warfare, or physical break-ins.

    Moving infrastructure to space solves local community disputes by removing the strain on residential power grids and freeing up land for housing or nature. Space data centers do not deplete Earth’s freshwater supply for cooling, unlike terrestrial centers which consume billions of gallons annually.

    Solar panels in orbit can access high-intensity sunlight 24 hours a day without interference from clouds, night, or the atmosphere.

    Data stored in space can exist outside of national borders, protecting it from seizure, censorship, or the legal jurisdiction of unstable governments. Data transmission can be faster in space because light travels roughly 30% faster in a vacuum than it does through fiber optic cables.

    Processing data directly in orbit is necessary for satellites and future space stations to avoid the delay and cost of beaming raw data back to Earth

    • While it’s true that there are no floods or earthquakes in space it’s not exactly a safe place to be. Radiation and cosmic rays become a much greater threat. Shielding provided by the atmosphere would have to be replaced.

      You also underestimate the cooling problem. The fact that space is cold doesn’t mean it’s easy to cool things off in space. On earth the main cooling strategy is to transfer heat through direct contact and move the hot stuff away. Be it air or water, as you mentioned. In space your only option is to radiate heat away. And that’s while half of you is under intense sunlight.

      I think you also undersell the thread of warfare in space. Sure, a guy with Molotov can’t get you space data center but we’ve had satellite shot down. So maybe not every war is a threat but, say China or Russia (or other space-faring nation) could take care of a satellite if absolutely needed.

      National seizures are also still a threat. If only being outside national borders was such a great defense we’d see some data centers in the sea by now.

      So being in space is immune to some of the known problems but also comes with a whole lot of novel issues, not solved at scale yet. And so far I haven’t seen any sufficiently detailed proposed solutions to even consider the trade of known problems with readily available solutions for new issues with lots of unknowns.

      • I am not saying it's viable or not. I'm saying that the statement the author put forward for why it's Absolutely not viable, is not valid.

        That's why I said I actually don't think it's realistic in my post. He might be right, but some of his reasons are wrong.

    • Every artificial satellite falls around the Earth in a little bubble of terrestrial national law.

      On the ground, legal notions of private property provide some legal protections against national government interference. But there is no private real property in space. 100% of the volume of space is subject to the direct jurisdiction of terrestrial national governments. Every artificial satellite persists only because they are permitted to do so by their national government.

      Because of the speed and energy involved, in the U.S. all private space activity is a matter of national security. This means that there are far fewer legal protections, not more. The U.S. president could directly order SpaceX to do almost anything, and they would have to comply. Musk spends tremendous energy and money maintaining alignment with the governments he needs to satisfy to stay in business.

    • Essentially all of your concerns concerns can be mitigated by building somewhere else.

      Worried about natural disasters? Build some place less prone to natural disasters.

      Worried about the strain on local communities? Build some place more remote.

      Worried about energy availability? Build near a nuclear power plant or hydroelectric power station.

      Worried about hostile governments? Don't build data centers within the territories of hostile governments. (If you consider every country a hostile government, that is a you-problem.)

      For the cost of building a data center in space, you could instead build a second (or third, or fourth, ...) data center somewhere else.

      • Omg. I dident say my reasons where good. I said that the claim that price vs ground based data center alone made space based compute a no God, was a bad argument. I obviously suck at framing my point
    • They may well avoid terrestrial threats by having them in space, but then they become subject to different threats such as solar storms, high energy cosmic rays, space debris collisions etc.

      I think the main reason to host them in space is to escape Earth jurisdictions, but even that is dubious as there will be people involved that reside on the Earth.

    • > Data stored in space can exist outside of national borders, protecting it from seizure, censorship, or the legal jurisdiction of unstable governments.

      You are aware physical persons exist on Earth and can be taken into custody? Additionally, space weapons exist, several governments could destroy any orbital satellite.

      This whole pipe dream is nonsense.

    • One of the bigger threats to life on earth right now is called Elon Musk.
      • That's the stupidest thing I heard so far to day.
  • I think the thing I often see missed in these discussions is the cost and time burden imposed by regulation. It's nearly impossible to build power plants in the US today. Launching satellites while hard, solves this problem.

    Even if it's more expensive, Spacex will be able to deploy hardware when no one else can because all the gas turbines and existing power plants have been exhausted and the lead time to build new ones is 5+ years out because of the bureaucratic overhead.

  • Surely, the question is: how big do the radiators have to be?

    gemini says that the NVIDIA DGX H100 is 130kg and takes 11kW.

    It says space-based radiators in the 100kW range are approx 15kg per kW. And space-based solar panels are approx 1kg per kW.

    So let's says we're talking about 1 system that bundles 9 DGX H100's. That's 1.2T for the computing system, 1.5T for the radiator, 100kg for the solar panels, and let's say 2T for the propulsion, propellant, guidance, and all the other spacecraft stuff. That's a total of about 5T, and the radiator is just about 20% of the mass budget.

    The power radiated is proportional to the 4th power of the temperature, so they would be incentivized to develop a heat exchanger with a high temperature working fluid.

    • I would assume that the current GPU systems are not optimized for weight. I would also assume that they need to build special purpose GPU equipment for space, which could possibly be made much lighter than the current ones.
  • The thing I find most notable is the lack of any concrete information on how these things are to be cooled, other than quotes like "space cooling is free".

    If you want to radiate away the heat, you are either limited by the Stefan-Boltzmann equation which requires extraordinarily large radiators at any reasonable operating temperature, or have to develop a "super-Planckian" radiator technology, something which while it may be theoretically possible doesn't seem to actually exist yet as a practical technology.

    The only other plausible technology I can think of would be to use evaporative or sublimation-based cooling, but that would consume vast quantities of mass in the process, every bit of which would have to be delivered to space first.

    Has anyone seen any published work that suggests it is actually anywhere near economically feasible to dissipate megawatts of power in space, using either these or any other technology?

  • What is the real-world advantage of putting datacenters in space?
  • Closest thing to a usecase I can think of are all military in nature. There's an argument that AI in space only begins to make any sense if the data source you are processing is also originating in space, and you need (for reasons) to run models on it in space before downlinking the results.

    Maybe there's a very latency sensitive need to send realtime targeting information to a tomahawk missile in flight? But it's also too bandwidth, compute or cost intensive to send a firehose of raw spy-satellite data to a disposable one-way attack munition?

    The data centers in space are actually for the spy satellites to use. That's all I got for practical applications.

  • You guys clearly didn't read the full blog post where Musk mentions lunar mining. They're going to put an ASML machine on the moon and turns regolith into chips and solar panels automatically. Literally free compute
    • If you believe that, you’re Musks target investor group.
    • I was skeptical until you mentioned this. Now I'm onboard
    • This is your brain on Factorio
      • I’m playing Space Exploration right now and all I can think is “damn what is he gonna do without productivity modules”
    • They’re going to have to deal with the moon nazis first. Oh no wait a minute.
    • Makes sense. I hope their plasma coolant supplies last long enough to get self sustained.
      • They'll just mine up Hemium-3 for that.
    • I can't even tell what's sarcasm anymore lol.
      • The comment you are replying to is definitely sarcasm… I hope?
    • Also cities in Mars, like who the fuck wants to live there?
      • Mars which is literally covered in poisonous perchlorate soil
      • >cities

        Not my downvote, I know what you mean.

        Much rather live way out in the boonies, as far away from civilization as possible.

        Oh wait . . .

      • I would, it would be an adventure.

        You could have said the same thing about Europe or America. We could have just stayed in Africa, and the people like you did. But taking the leap worked pretty well, even if it was tough at the beginning.

        • Africa, Europe, America, Mars. I wonder if there is something about one of these that makes them unlike the others.

          Actually, why not colonize Venus instead? Sure, it will be hard, at first, with all the sulphuric acid and intense heat and whatnot, but we colonized America, so why not Venus?

        • Would you say that slaughtering Native Americans and enslaving Africans "worked pretty well" for them, or do you only speak from the White adventurer perspective?
        • I'd rather colonize antarctica than mars.
      • We can't keep our already perfect planet livable, but we're going to terraform a totally new one. Yeah right buddy.
        • It'd probably be easier to terraform than convince everyone it's possible.
        • Earth keeps getting more livable!

          We have a record high population, healthier and richer than ever.

        • You seem to be alive? So....
  • The Kessler syndrome is mentioned, satellites colliding, causing a cascade of follow-up collisions. This gets brought up a lot, but people have a poor intuition on how large the orbit space is. Think of it this way: It's obviously larger that Earth's surface, and placing, say, a million objects on Earth still leaves a lot of space between them (there are thousands as many humans). Yes, satellites move in certain orbits, not in random places, but space is large, and humans are bad with imagining large numbers and things. The illustrations with fat dots on tiny earth images are misleading too IMO.

    Apart of that, I do agree that space data centers are probably just a marketing stunt at this point, although some things could obviously be done to increase their chances, like more lightweight designs on GPUs, something that was never a big topic before.

    • The other way people get confused about Kessler syndrome is that they imagine it's like the movie Gravity where it happens suddenly rather than a slow process that plays out over years/decades.
  • I loved when we would have an HPC server crash and we would analyze the issue and the vendor would respond, "probably a neutrino strike". I can't imagine this being more complex, given all the constraints of being in an orbit. The hardware depreciation, and the need to eliminate charge buildup and excess heat. Placing servers in the Arctic seems a better solution, at least the cooling issue is resolved.
  • As a thought experiment, if humanity wanted to go all in on trying to move industrial processes and data centers off planet, would it make more sense to do so on the moon?

    The moon has:

    - Some water

    - Some materials that can be used to manufacture crude things (like heat sinks?)

    - a ton of area to brute force the heat sink problem

    - a surface to burry the data centers under to solve the radiation problem

    - close enough to earth that remote controlled semi-automated robots work

    I think this would only work if some powerful entity wanted to commit to a hyper-scale effort.

    • The Moon also has 14 day long nights, while space has permanent sunlight for your solar panels.

      I suspect this is really the fundamental idea behind this whole plan.

    • Water on the moon is limited and difficult to collect, it wouldn't make sense to use it for industrial purposes. It's a very challenging thermal environment (baking during the day, freezing at night). But perhaps worst of all, every month there's a 14-day period with no solar power. Overall seems worse than low-earth orbit.
      • > every month there's a 14-day period with no solar power

        So it's dark 50% of the time on the moon... just like here on Earth.

        • ... and completely not like a sun-synchronous Earth orbit which is dark 0% of the time.
    • Probably a lot easier, but the moon looses a major selling point of data centres in space, namely reasonable latency. To be clear, I don't think it's a good idea. But I think that specifically the way Musk is trying to position it, the moon would be an even harder sell.
      • > But I think that specifically the way Musk is trying to position it, the moon would be an even harder sell.

        I agree. I would be quite a moonshot.

    • it could be easier just to build in orbit. its a lot closer, sites can be positioned above various geographic locations as required.

      i think the moon likely does contain vast mineral deposits though. when europeans first started exploring australia they found mineral anomalies that havent existed in europe since the bronze age.

      the Pilbara mining region is very cool. it contains something like 25% of the iron ore on earth, and it is mostly mined using 100% remote controlled robots and a custom built 1000 mile rail network that runs 200-300 wagon trains, mostly fully automated. it is the closest thing to factorio in real life. 760,100 tonnes a year of iron ore mined out and shipped to China.

      • And Fortescue and others are working on BEV vehicles for those giant Tonka trucks that move the raw ore to the processing areas at the top of the opencut.

        They were also working on a "zero energy" train that would run "downhill" from the mines to the ports to charge its batteries that would then take the empty train back to the mine.

        Battery tech wasn't sufficient (yet), but that doesn't mean it can't come back when solid state and sodium ion batteries come online.

    • The elephant in the room for all lunar scenarios is lunar regolith. Even ignoring the toxicity to humans (big problem and will happen quite quickly for any humans there!), it will be a big long-term problem for robots and machinery in general.
    • Best bet is to put the servers in a rocket, go around the moon then land back on earth. Then install them in USE1.
    • What if instead we moved it all to a closer rock that has even more water, even more materials to manufacture crude (and even advanced) things, even more surface, more protection from radiation, and even crazier still had significantly less launch costs?

      Almost any reason why the moon is better than in orbit is a point for putting it on earth.

      • I think there's something to be said about imagining a future where we can keep the earth clean of all the nasty industrial processes we have grown accustomed to living next to. A big part about this proposed idea is that you could do a lot of manufactoring in space.

        I have long theorized there will be some game changing manufacturing processes that can only be done in a zero gravity environment. EX:

        - 3d printing human organ replacements to solve the organ donor problem

        - stronger materials

        - 3d computer chips

        I do not work in material science, so these crude ideas are just that, but the important part I'm getting at is that we can make things in space without any launches once that industry is bootstrapped.

        • Human organs manage to grow pretty well in 1G. In fact, they're almost certainly going to be terrible at it in zero g.
        • We're able to make 3D computer chips on Earth today, and I don't know about you but all my organs managed to get made just fine on Earth. Doesn't seem like we need zero g to do either of these things.

          Either way, this isn't about 3D printing organs, this is about launching AI compute into space. To do important stuff, like making AI generated CSAM without worry of government intervention.

          • The first two kidneys are free its the third one that gets tricky
  • As far as I can tell, Data centres in space only seem viable because their advocates insist on comparing them to standard terrestrial data centres.

    And nobody ever calls them out on it.

    Today's data centres are optimised for reliability, redundancy, density, repairability, connectivity and latency. Most of advertised savings come not from placing the data centre in space, but the fact that advocates have argued away the need for absolutely everything that modern data centres are designed to supply, except for the compute.

    If they can really build a space data centre satellite for as cheap as they claim, why launch it? Just drive it out into the middle of the desert and dump it there. It can access the internet via starlink, and already has solar panels for power and radiators for cooling. IMO, If it can cool itself in direct sunlight in space, it can cool itself in the desert.

    The main thing that space gains you over setting up the same satellite in the desert is ~23 hours of power, vs the ~12 hours of power on the ground. And you suddenly gain the ability to repair the satellite. The cost of the launch would have to be extremely cheap before the extra 11ish hours of runtime per day outweighed the cost of a launch; Just build twice as many "ground satellites".

    And that's with a space optimised design. We can gain even more cost savings by designing proper distributed datacenter elements. You don't need lightweight materials, just use steel. You can get rid of the large radiators and become more reliant on air cooling. You can built each element bigger, because you don't have to fit the rocket dimensions. You could even add a wind turbine, so your daily runtime isn't dependant on daylight hours. Might even be worth getting rid of solar and optimising for wind power instead.

    An actual ground optimised design should be able to deliver the same functionality as the space data centre, for much cheaper costs. And it's this ground optimised distributed design that space data centres should be compared to, not today's datacenter which are hyper-optimised for pre-AI use cases.

    -------------------

    Space data centres are nothing more than a cool Sci-Fi solution looking for a problem. There have been mumblings for years, but they were never viable (even bitcoin mining was a bit too latency sensitive). Space data centre advocates have been handed a massive win with this recent AI boom, it's the perfect problem for their favourite solution to solve.

    But because it's a solution looking for a problem, they are completely blind to other solutions that might be an even better fit.

    • This is the correct analysis.

      Not to go all Ian Malcolm, but half this comment section is spending so much time wondering if we could build a space data center, without stopping to ask if it made any goddamn sense whatsoever to do so.

    • By keeping the whole thing on earth we can also reclaim the gold, copper, and rare earth metals when it’s financially viable to do so, rather than just letting them burn up on reentry.
    • You don’t even need the desert. Just put it in India and use coal power or whatever. AI training doesn’t care about latency to the data centre, so you could put it anywhere, as long as it is cheap.
      • I mean, I'd prefer they used some form of renewable energy.

        But there should be plenty of options once you start actually optimising for the same use-case as space data centres. Many places have very predictable wind (especially off-shore, which gives you bonus access to cooling water). Or maybe you could set up small hydro power schemes along remote rivers.

        • After the last round of this a few weeks/months ago I realized: Assuming the investors for this are too stupid to do the figures seen here themselves is folly. So, they must be factoring in something else-

          Perhaps space based DCs allow for expansion into ITAR controlled countries and/or sanctioned countries/individuals.

          Maybe throw in the fact that nobody can REALLY verify system behavior once its up there. So NSA/CIA etc sure are chomping at the bit to allow it.

          I'm sure there's others I haven't thought of- probably less outlandish/tinfoily as well.

  • Data centers in space make no sense because cooling things in space is insanely hard!

    Yeah, space is cold, but also you don't have access to large thermal masses with which to exchange heat, so the fact that space is cold does not help much.

    In space the only option for cooling is large radiators. If you had a data center in space you'd need enormous radiators -- much larger than the data center itself.

    (On Earth we can exchange heat with the environment, and the environment includes convection and the water cycle and ultimately can expel excess heat via high altitude condensation of water vapor where most of the heat released escapes to space. As well clouds can both block insolation as well as keep heat below trapped, but altogether between high altitude condensation and blocking insolation this is the mechanism by which Earth keeps its temperature as a random walk around the average that we enjoy.)

  • As others point out this is a bad idea.

    Asside from the other excellent comments on power consumption, cooling and radiation. One point I didn't see being made in the comments much is maintenance costs.

    Now I don't find myself in the facility of a data center often in daily life, however I do know that medium to big data centers require 24/7 hardware replacement. I believe this is what those 5 guys with the bikes and scooters are doing in every data center. That would be very difficult, near impossible in space (with the current space fairing infrastructure).

    • Do those people actually _repair_ hardware, or do they swap bad hardware for good chips?

      Can SpaceX not just say "OK, GPU #7 on satellite #15872 is broken, don't use it" and just accept that they're now overbuilt on power/cooling for that sat?

      • From what I understand it is in part swapping it, in part upgrading it. Some of it is preventative some of it is reactive. They could overbuild the hardware and slowly disable capacity I think that will not really work. Data centers are static in infrastructure but not in the systems running within them. Actually they are constantly changing to meet the needs.

        Overbuilding also comes with a cost when talking about space, it is still very costly to get stuff up there and there is limited bandwidth downstream, you want to balance those two. So if you're overbuilding it costs a lot to get up there, if you disable what's up there you don't fully utilize the bandwidth.

        For example AI data centers now use very different hardware compared to 5 or 10 years ago that upgrade path is just a lot harder when your data center is in space.

  • I think what many people miss is that energy became far less location dependent if you put compute next to its generation. The latency for token generation is not so important. So the ratios between energy consumed, bandwidth and latency would in theory favour building dark token factories in remote but optimal locations. But i guess construction and logistics are an issue.
  • Back when I worked at AWS, I wrote a one page “press release” about this concept where the value add was the weight/power reduction of customer sats that could offload on board processing to the “Cloud above the Clouds”. There is a bottleneck with the down/uplink ground stations to do the on the ground processing.

    The biggest problem folks had was even with equipment with 99.9% reliability something breaks every day due the huge raw number of devices involved. And most network equipment is not any where close to being radiation hardened.

    I had some fun with it with Bezo’s fist bumping folks because SpaceX was cleaning BlueOrigin clock.

    I talked to one of their lawyers and didn’t hear anything afterwards. I left AWS and a couple of years later Amazon announced AWS ground station. I wonder how much my paper contributed to green lighting that project.

  • To Steelman the topic, Musk’s whole alleged mission is to make humans a multi-planet species that can survive an earth killing event.

    To that end, a small data center space isn’t about unit-economics, it’s a bigger mission. So the question we should consider is what can we put into space the further that mission. Can we put a meaningful sum of human knowledge out there for preservation? It sounds like “yes,” even if we can’t train ChatGPT models out there yet.

    • When I was a kid, I had to go to CCD, a religious after school program for Catholics.

      The whole time I was there it was a mental game of trying to steel man the contradictory or incoherent stuff, using my brain power to try and rewrite things to make sense.

      After some years, I woke up and realized that’s what I was doing, and even if I could do it in my mind, that didn’t make the source material rational.

      Heres hoping you have a similar moment.

      • Pseudo-psychoanalyzing someone for explicitly steelmanning a subject seems particularly degrading to discussion.
      • > Heres hoping you have a similar moment.

        I do not politically align with Musk. I’ve always thought Tesla was important in popularizing electric cars while being a low-quality built product with repair and supply chain issues. I think The Boring Company is a joke. Twitter was a power-grab.

        I also think SpaceX is societally beneficial, a good means to shake-up a stagnant industry and a humanity-wide area of interest.

        If you think I’m a member of a religious cult, I respectfully suggest you evaluate what led You to believe that itself.

        • I completely failed to convey my point. It’s not about any of your beliefs.

          The point is that you have been handed a pile of incoherent hog wash, and you are using all the powers at your command to rearrange it into a coherent narrative. It’s like a mental game that some of us cannot help but play. The point is you have to realize you are playing a game, in your head, and even if you can make a beautiful pattern out of the noise, it was still just noise.

          Where there is actual meaning in life, its kind of obvious, you dont have to rewrite so much to find it.

          • > ...you are using all the powers at your command to rearrange it into a coherent narrative...

            You're literally describing steelmanning, which GP explicitly set out to do.

            > It’s like a mental game that some of us cannot help but play.

            Despite attempting to rephrase, you're still coming across as projecting your own internal issues onto GP's comment. Directly addressing the (worthwhile) points they made in their comments rather than attempting to analyze the meta of the basic nature of someone you've never met is the way to go.

    • The problem of datacenters in space and knowledge preservation/disaster redundancy are entirely disjoint.

      Datacenters in space have a lifespan measured in years. Single-digit years. Communicating with such an installation requires relatively advanced technology. In an extinction level crisis, there will be extremely little chance of finding someone with the equipment, expertise, and power to download bulk data. And don't forget that you have less than a decade to access this data before the constellation either fails or deorbits.

      Meanwhile people who actually care about preserving knowledge in a doomsday crisis have created film reels containing a dump of GitHub and enough preamble that civilizations in the far future can reconstruct an x86 machine from scratch. These are buried under glaciers on earth.

      We've also launched (something like) a microfilm dump of knowledge to the moon which can be recovered and read manually any time within the next several hundred or thousand years.

      Datacenters in space don't solve any of the problems posed because they simply will not last long enough.

    • Let's say there is an earth killing event, and let's say there is an outpost on Mars with some people on it. How much does it really matter that some humans survive, in light of the enormous catastrohophe that killed all life on earth? Is it a very worthwhile objective for our species to persist a while longer, or should we not just accept that also life itself will will die out on geological or astronomical time scales?
      • I would suppose there is a gap we face between true species-wide survival capability and where we sit today. I have no true idea how hard we must go to bridge that gap, but it’s quite hard and far.

        I also see no reason to “lay down and die” as I feel is somewhat implied here. I think it’s a truly noble cause, but maybe I read too much sci-fi as a young lad.

        • No matter what anyone does, the universe will end, and reality will stop changing.

          Everything dies. Deal with it.

          Instead of empowering shithead grifters who promise you a way out, grow trees to create shade for people you will never know. You do that by improving things, not burning limited resources on a conman.

          • If this outcome is guaranteed, why hasn't it already happened ?
            • Because we exist inside time, not outside it.
            • Same reason you're not dead yet.
            • How do you know it hasn't?
      • The whole point of the space stuff is not accepting all life dying out on any timescale.
        • Even rocks don’t last. What do you expect?
    • A data center in space is probably toast after some years of space radiation.

      High performance chips are made for the shielded atmosphere. Imagine the cost launching all the extra shielding that you don't need on earth.

      It is beyond stupid. Comical levels. I can't believe people are trying to find any justification.

      • I’m not the right type of engineer to know and, hell, software largely isn’t engineering anyway…

        Can you not provide any type of shielding at scale to wrap a (small, not Google tier) data center? To be honest my criticism with TFA is its focus on “you can’t do massive scale” rather than the premise entirely.

        • Yes, but the added mass makes it prohibitively expensive. Shielding is heavy and every kilogram of added payload results in a geometric increase in fuel load.

          The rocket equation will kick your ass every time.

    • If that's really the case: wouldn't merging or collaborating with Nvidia make more sense then with xAI?
    • Musk's whole mission is to scam even more people. Unfortunately people still buy his bullshit even though he couldn't deliver on anything, and just converts one failure to hyping up his next idiotic product.

      (Yes, I know what steel manning is)

    • Sure but you could do that with a simple disc in space
      • Actually, the data centers can be the discs. As long as the data centers can crunch on, we don't need to stay alive here on earth
    • A sum or product of human knowledge is not humanity: that specific mission (putting it into space for preservation or contact) has been done (Voyagers and others) and is done continuously (radiowaves).

      Making a dent into making humans a multiplanetary species requires making a lot of companion species as well; the task requires much more elementary stuff (relative to the mission), at the ground level, than Musk is demonstrating to do (at technical, entrepreneurial and political level).

      This is a con, from the start. It just worked so far so some people fall for it.

  • One way to work around the heat dissipation issues in space (and also on earth) is to move to computing systems that operate entirely at cryogenic temperatures to take advantage of superconducting circuitry.

    I've heard stories that over a decade ago teams inside hyperscalars had calculated that running completely cryogenically cooled data centers would be vastly cheaper than what we do now due to savings on resistive losses and the cost of eliminating waste heat. You don't have to get rid of heat that you don't generate in the first place.

    The issue is that at the moment there are very few IC components and processes that have been engineered to run at cryogenic temperatures. Replicating the entirety of the existing data center stack for cryogenic temps is nowhere near reality.

    That said, once you have cryogenic superconducting integrated circuits you could colocate your data centers and your propellant/oxidizer depots. Not exactly "data centers off in deep space" since propoxd tend to be the highest traffic areas.

    • by my calculations, the heat dissipation isn't that big a deal

      take an h100 for example. it will need something like 1kW to operate. that's less than 4 square meters of solar panel

      at 70C, a reasonable temp for H100, a 4 square meter radiator can emit north of 2kW of energy into deep space

      seems to me like a 2x2x2 cube could house an H100 in space

      perhaps I'm missing something?

      • Heat travels when there is a thermal gradient. What thermally superconducting material are you going to make your cube out of that the surface temperature is exactly the same as the core temperature? If you don't have one, then to keep the h100 at 70c, the radiators have to be colder. How much more radiator area do you need then?

        Have you considered the effects of insolation? Sunlight heats things too.

        How efficient is your power supply and how much waste heat is generated delivering 1kW you your h100?

        How do you move data between the ground and your satellite? How much power does that take?

        If it's in LEO, how many thermal cycles can your h100 survive? If it's not in LEO, go back to the previous question and add an order of magnitude.

        I could go on, but honestly those details - while individually solvable - don't matter because there is no world where you would not be better off taking the exact same h100 and installing it somewhere on the ground instead

        • h100 can operate at 80-90C continuously, so 70C seems conservative

          I'm not advocating for space GPUs as a logical next step. so many unsolved problems remain

          point is that launch costs per kg are a more realistic blocker than cooling

      • The typical GPU cloud machine will have 8 H100s in a box. I didnt check your math but if a single machine needs 32 square meter radiator, 200 machines will probably be the size comparable to the ISS.

        How much does it cost to launch just the mass of something that big?

        Do you see how unrealistic this is?

        Given that budget, I can bundle in a SMR nuclear reactor and still have change left.

        • my point is that cooling is not the problem, launch cost per kg is
  • AI data-centers use upwards of 100MW. The biggest solar panels in space could produce around 240KW. When they speak of AI data-centers in space what do they actually mean in realistic non theoretical terms and where are the materials for this coming from?

    If the AI data-center used only 10MW then each could have two redundant SMR's assuming the cooling challenges have been worked out but then we could have nuclear reactor disposal and collision issues.

    • This is the thing I don’t get. Everyone talking about the “how” but nobody talking about the “why”? It makes literally no sense.
      • The only thing that keeps bouncing around in my thick skull is something "data-center sized" whatever that means to them could hold some interesting objects. 2 Peta Watt laser, Rods from God, Tactical nukes, Miniature Rail-gun to quickly eradicate other satellites, Off-Planet archives of stuff, Doomsday clusters of brainwave transmitters to shut off all the humans or force everyone to defecate at once.

        Those are just some guesses. Some of those could also explain the "why" for SpaceX Falcon Heavy and it's future iterations. It can carry 63,800 kg (140,660 lbs) to Low Earth Orbit and that load capacity will only increase with future versions.

      • Because people have to compete just to have sand doing math for us? The why is that it's high time we stop worrying about how much compute we have. Certainly filling all solid planets in the solar system with computers is not nearly enough computation as we want (I'm not even talking about AI specifically).
      • Snake oil, like bitcoin.

        A lot of people will invest in this because "it's the future" and a few will make a lot of money on that.

    • I assume the idea is to have the entire constellation be the data center in question. Laser back haul transceiver bandwidth is in the same order of magnitude of rack-to-rack bandwidths [1][2]. I could see each sat being a rack and the entire mesh being a cluster.

      [1] https://hackaday.com/2024/02/05/starlinks-inter-satellite-la... (and this is two years ago!) [2] https://resources.nvidia.com/en-us-accelerated-networking-re...

      • This is how Starlink works however, you would need orders of magnitude more compute than those router pucks. Orders of magnitude more power needs unless you combined a nuclear reactor to it. It’s just such a fever dream at this stage that he’s really doing it to muddy accounting and consolidate debts from Grok failures.
      • For AI training, latency is one of the limiting factors, which needs to be kept in the nanoseconds. And a light-nanosecond is famously almost exactly 1 foot.

        That's why Lumen/Starcloud's designs all assume it'll be a space station with all containers connected to one central networking spine.

  • How do you protect a datacenter in space from evil nation states that have an appetite for your GPU cards?
  • It's a scam for investors.

    The self-driving car worked too well. Tesla is promising that for over a decade now, and still can't deliver. They came much closer to the goal, but are still very far away from it. Shareholders don't seem to care.

  • They're gonna propose something dumb like ejecting coolant out into space as a disposable heatsink and then they're gonna spend a bunch of money trying to build a proof-of-concept but it will never go anywhere because it's really some kinda money laundering scheme or whatever the Hyperloop nonsense was.
    • Musk said in his autobiography he announced the hyperloop plan without any intention of doing it to distract from the California high speed rail plans.
  • By combining ai with space, in addition to any other plays that he might be playing around legal or financial areas, he's positioning (marketing) spaceX for the bandwagon that everyone else might jump into to deploy a space datacentre. He's providing the medium (spacex rockets) to realise this potentially unfeasible idea. He makes additional money that way - to then create a new type of money-making fuel after that. HN audience might be calculative - but the rest of the population is far less so.

    This might also be a new vehicle to mask any space warfare technology deployments.

  • It seems like every argument in favor of doing this is: "yeah sure but what if X was Y% cheaper?"

    And some of us are reading these things and trying to be polite.

    But at some point patience runs thin and the only response that breaks through the irrationality is some variation of "what if unicorns and centaurs had teamed up with Sauron?"

    The limit of the ratio of useful:useless "what if's" approaches zero.

    • With regards to a community, I once heard someone say that it takes 10 "atta boy"'s to counteract 1 "you suck".

      I also remember, roughly 10 years ago, people saying that the amount of effort to discredit bullshit is wildly out of whack. Which makes bullshit basically asymmetric warfare.

      So here we are, in this thread, actually spending time attempting to discredit bullshit.

  • I'm sorry I really don't understand this. I have a computer. I put it in a warehouse. You have a computer, you shoot it into space. What problem have you solved?

    Is this all an effort to utilize more efficient solar panels? Are solar panels really the limiting factor for data centres?

    • I think some people like this because it pushes libertarian "no need for environmental or regulatory review" buttons. There's a kernel of a valid argument there, but it seems overstated given that companies seem to have little trouble getting approval for big datacenter buildouts here on earth.

      There's also the coolness factor, I guess.

      But why does no one talk about launching RackSpace servers into space? I think the whole thing is tied to AI because of the hype, not because sending servers into space has any kind of material advantages.

      • Not to mention the fact that you trade one source of pollution for another. You think giant rockets to lift tons of equipment into space is good for the environment?
  • Until someone actually launches a prototype, this is not happening. The economy of just doing everything on the ground is underestimated. And the technology simply is still not ready. LEO sats randomly falling down is a daily occurrence. I would love to see the Excel spreadsheet these investors are drooling over. It probably has less than 6 tabs.
    • This is the same guy that had his followers preach about how cars in tunnels for public transit is better than… trains in tunnels… Do not expect logical arguments when dealing with this guy and his followers.
  • It makes sense if you want low-latency compute accessible to other things in space making use of it: Pharmaceutical research, manufacturing. These are large, non speculative areas of likely growth in the space industry. Manufacturing especially will require lots of inference compute with the AI systems currently under development for industrial robotics.

    If you're looking at this and saying "Lol, no, we don't need data centers in space just to power more GPT sycophancy and some health insurance company's RAG workflows." Then you're right, so just move on from that usage and consider the things we'd like to do in space, and especially the things we're already doing but want to do more of.

    I know, my gut was telling me this is ridiculous, premature at best even through the lens of expanding space industry. But then with respect to the need for data centers-- had I even thought about it a year ago, my gut would have laughed if someone had said "Buy Wester Digital, HDD's are a growth stock".

  • Starship payload: 100,000 kg (100 tons). Looks like they talked about 150 tons and even 250 tons. My understanding is that they can be adding more engines to get more thrust.

    https://www.nextbigfuture.com/2022/02/spacex-reusable-rocket... -- looks like target price for Starship launch would be $3--$5m according to the author.

    Wouldn't the /kg price to SpaceX be:

    3000000/100000 = $30/kg -- 5000000/100000 = $50/kg?

    If they recover everything and produce fuel at scale, wouldn't it drop the cost even more.

    What many people quote here are commercial rates, I think. SpaceX won't pay those prices.

    Can someone check my math

  • How about we just make a giant heatsink that reaches into space instead. Then we can cool the whole planet. Coming up with crazy ideas is cheap, but the logistics are obviously impractical.
    • 0x53
      Look into radiative cooling. Basically this, but more practical. Several companies working on it: https://www.skycoolsystems.com/
      • I don't quite believe this.

        Is it really better than just using solar panels to run a heat pump?

        • > Our core innovation is a radiative cooling material that we’ve combined with a panel system to improve the efficiency of any vapor-compression based cooling system

          A heat pump is a “ vapor-compression based cooling system” so that tech is an addition-to not an instead-of.

          Whether it’s better probably depends on how expensive the additional efficiency is in practice.

          > SkyCool’s Panels save 2x – 3x as much energy as a solar panel generates given the same area.

          So if you’re area constrained maybe.

          • That's very hard to believe. Radiative cooling is really bad compared to any kind of fan in front of aluminum fins.

            Air itself is an isolator, there is a reason you need to shove in fresh air to take on more energy from the heat source.

      • This looks like it depends on the outside air to cool the coolant. "Radiative" can mean that too, not just IR radiation.
    • We had one. It was that sulphur used in shipping fuel.
  • It possibly makes sense if you're preparing for war, harder to hit, harder to physically break into, beyond the range of nuclear EMP, and accessible from anywhere on earth.
    • > harder to hit

      press x to doubt

      > on 21 February 2008, the US Navy destroyed USA-193 in Operation Burnt Frost, using a ship-fired RIM-161 Standard Missile 3 about 247 km (153 mi) above the Pacific Ocean.

      https://en.wikipedia.org/wiki/Anti-satellite_weapon

    • Any country capable of producing nuclear warheads will also be able to toss up enough BBs and other small objects into LEO to wipe out most of Starlink and anything else in LEO. At least on Earth data centers in theory can be hidden and physically hardened. In orbit, even a crude rocket able to reach that plane can become a weapon of mass satellite destruction. Even if those orbits clear out in four or five years, by then whatever ugliness is going on down on the surface of Earth will likely have resolved one way or the other. Starlink is a great military asset for a superpower pushing around smaller states in ways that aren't an existential threat to them. In a real conflict, it's a fragile target beyond the strike capacities of much of the developing world but easily destroyed by any moderate level industrial nation.
      • Any country capable of producing nuclear warheads will also be able to toss up enough BBs and other small objects into LEO to wipe out most of Starlink and anything else in LEO.

        South Africa built nuclear weapons in the 1980s:

        https://en.wikipedia.org/wiki/South_Africa_and_weapons_of_ma...

        But it never had an orbital launch capability.

        Pakistan doesn't have a domestic orbital launch capability but it does have nuclear weapons.

        Surprisingly, the United Kingdom doesn't have a domestic orbital launch capability at present though it has had ballistic missiles and nuclear weapons for many decades.

        At present, I would say that building a basic implosion-assembled atomic bomb is easier than building a rocket system that reach low Earth orbit. It's a lot easier to build a bomb now than it was in the 1940s. The main thing that prevents wider nuclear weapon proliferation is treaties and inspections, not inherent technical difficulties.

        • presumably the UK could figure out how to remove the top of a trident missile and replace it with a load of ball bearings
          • Tridents can reach mach 19. Orbital velocity is more like mach 100.

            Not that the UK manufactures trident missiles anyway.

            • 27720km/h orbital velocity is Mach 22.4 at a sea level speed of sound
            • You don't need orbital velocity to blow satellites away. Just do a well-timed suborbital launch against the satellite's orbit, and the satellite will provide most of the kinetic energy.
            • if only you could put some sort of explosive charge on the top
            • Orbital velocity is nowhere near mach 100.
        • You do not need orbital capability to hit an orbital target. Just suborbital missile that reaches target's orbital altitude.
      • Satellites. Are. Fragile. People really don’t seem to intuitively understand this. Earth based assets are orders of magnitude more difficult to attack simply by virtue of being able to be placed inside of fortified structures anchored to, or inside of, the ground. The cost to deploy hardened buildings at scale is peanuts compared to orbiting constellations.
      • They also fail to realize how devastating an attack a BB canister grenade would be in LEO. Nothing would stay in orbit. Eventually everything would collide and come down.
        • LEO is big, really big. Even at the smaller radius of ground level, large volcanos, forest fires, etc. Don't affect the whole earth.
      • Isn't the eventual plan to park these data centers out by the Lagrange points?
    • You don't need EMP for that. Few ASAT missiles will start the avalanche and turn orbits around Earth into shooting range. Good luck talking to your satellites with shredded antennas and solar panels.
  • There are plenty of legit concerns here about e.g. the launch externalities which are actually greater than the launch costs themselves, i.e. climate impact to future generations.

    However one flaw in this critique is that is only looks at the cost of ground-based solar panels and not their overall scalability. That is, manufacturing cost is far from the only factor. There is also the need for real estate in areas with good sun exposure that also have sufficient fresh water supply for cleaning.

    When we really consider the challenges of deploying orders of magnitude more terrestrial solar, it really requires a more detailed and specific critique of the orbital vision. Positive includes near continuous solar exposure (in certain orbits) and no water requirements.

    Much has been said of cooling but remember, there is a lot of literal space between the satellites for radiative cooling fins. It is envisioned they would network via optical links, and each mini satellite would be roughly on the order of a desktop GPU (not a whole data center rack). The vision is predicated on leveraging a ton of space for lots of mini satellites on the order of a Dell desktop tower. The terrestrial areas that are really cold are also not that great for solar exposure.

    Personally I don't know how it will play out but the core concern I have about making these kinds of absolutist predictions is they make weak assumptions about the sustainable scalability of terrestrial power. And that is definitely the case here in that it only looks at the manufacturing cost of solar.

    • > There is also the need for real estate in areas with good sun exposure that also have sufficient fresh water supply for cleaning.

      Solar panels are 20x more efficient than growing corn for ethanol. Swap out some of those 30 million acres of ethanol corn fields (in the US) and you'll have more energy than you need.

      More details here: https://www.youtube.com/watch?v=KtQ9nt2ZeGM

      • Utility scale PV farms should be seen as literally harvesting solar power, not generating it, while still allowing other agriculture like sheep grazing to occur using the same fields.

        You plant a PV panel and add its irrigation (power interconnect) and remote monitoring, then you harvest power for the next 25+ years.

        Ethanol production excess is a specific US problem because of the misalignment of incentives and lobbying.

      • I’m all for it — converting just a third of that land to solar would be enough to power the grid in terms of raw output — but there is still a huge, unsolved problem of energy storage that scale. Without that you’re only powering your data center for five hours a day.
  • I wonder if the author was making similar arguments against solar power 20 years ago. The case for both isn't one of immediate ecenomic advantage, though that may come with sufficient development like solar has had. If you take it as a given that compute demand continues scaling, at some point we will need to shift power generation off Earth, and it's a lot easier to move computed data streams instead of terrawatts of power.
  • My dark theory is that the goal is to run an AI overlord in space such that it is difficult to counter it from Earth.

    If you assume that these people aren't completely stupid, then there is some reason why they want this workload running at great physical distance from all the people down on Earth. It's probably not to protect people on Earth. After all they'll happily deorbit satellites and other junk from orbit and let it rain down on us. And they will happily destroy the environment with all those rocket launches too. Therefore it must be to protect the workload from us.

    What is a workload that is something that people would probably want to destroy, and which would also provide enough value to offset the expense to launch and run in space? The only thing that might make sense is a military AI platform. Think something that observes Earth, launches missiles, and controls terrestrial drone armies remotely, with relatively low latency.

    It gets built and launched thanks to endless military budget, and once it is up there, running such an AI from space means that effectively the only people who can take it out are nation state level foes who can launch rockets into low earth orbit. And this thing is a satellite, probably part of a network that is watching the Earth all the time. Start building something that looks like a rocket launch site, and the AI will see, then you get hit by a missile or taken out by a drone first before you get a chance to attack the platform.

    It sounds like sci-fi, but in the future, if we let it happen, there could absolutely be nearly invulnerable autonomous AI platforms in space overseeing everything, and making decisions, and issuing commands. Of course there could still be a massive solar flare event, or a Kessler syndrome event that releases us all from AI enforced servitude. Anyway, it's a not so fun thought experiment, and let's hope this stays sci-fi, so we can just enjoy a fun Hollywood film about this rather than experiencing it firsthand.

  • One major point I haven’t seen mentioned is maintenance.

    Nvidia GPUs, particularly H100s, have a failure rate orders of magnitudes higher than traditional CPU-only hardware. I myself have accidentally melted an H100 during a large-scale training run.

    While it’s trivial to replace a broken GPU in the ground, it seems to be infeasible in space during the life of the satellite. Getting a human or robot “fixer” spacecraft to it would likely cost more than the $30K GPU itself.

  • This whole thing is Musk just trying to keep the hype train going. Musk has learned one neat trick from all of his (quite admirable) success with Tesla and SpaceX: hype is more profitable than actually doing stuff that generates value now.

    Tesla's valuation has been nuts for a while. The music was going to stop playing at some point, so something something robotaxis, something something androids, something something AI. Keep the investors duped while you can move money around and leverage it to stay relevant.

    Cars are out, social media as well (especially X), but Space is still in, and even more so AI. So let's move the cost center with world domination potential (AI) over to the one company that's making money and has a still has a cash-out potential via an IPO.

    I'm just so tired of it all. I actually think 'boutique' businesses (companies that generate real value to real users and are profitable now) are the only thing that can save our economy medium-term, but investors and the government are having none of it. And the result is that these bait-and-switch scams will continue.

  • I had this idea in the beginning of last year and since I wanted to somehow get into space infra started doing some calculations - the area of arrays required kinda made me scrap the whole thing. But kinda curious since this is back as a mainstream topic.
  • I have my personal reasons to hate Elon. But the article is full of fluff and lacks imagination, typical of the "the world is static and will never change" mindset.

    What they are trying to do is an a very ambitious engineering challenge in several highly integrated domains, from spaceships to robotics, gpu, server design , ai. Typical stakes are high margins are high.

    Project also pushes boundaries of what human can do the same way starlink did. 20 years ago starlink scale was also an "impossible" thing. Is it possible now to push one gpu and serve it from space? Yes, can you do it at scale? Big question.

    Obstacles :

    Price per kg to orbit. They aim to go from $150 to $10 per kg. Can they deliver? Big question, but having something that demands so many starship, like GPU heavy tasks, will help them achieve this goal. Benefits? No rent, no cooling issues, cheap sun-powered electricity 24 hours a day, unlike anywhere else on Earth.

    Jurisdiction. Servers can't be shut down or taken away by police, etc.

    Cooling. Yes, it's a vacuum, but with $10 per kg, you can deliver pipes and coolant, and since you don't have space constraints, you can build these pipes with a robot, making that datacenter extremely cheap.

    3. Labor. If a robot can do primitive tasks combined with design that is fully remote, you labor costs goes almost to 0.

    the output: with $10 per pg, delivering solar panels, coolant + robot for some urgent fixes. Robots even with current technology can swap a harddrive for example, especially if hardware is built to be mantained by robots not human. You don't need large construction, you invest into design, that once assembled , cost you maybe comparable amount of hardware to deliver. After that it runs for free!

    The economy if this obviously beating anything exised on earth.

    • Elon is that you?
    • > Jurisdiction. Servers can't be shut down or taken away by police, etc.

      Total pipe dream. They can't take away your servers, but they can imprison you until you provide access. And SpaceX would still fall under the laws of whichever country it's based in. If lawful access is really a problem, laws will be written to make it SpaceX's problem. Relevant XKCD: https://xkcd.com/538/

      • yes... and no. Right now you need a server lets say in france. You are fully in their jurisdiction, for latency etc.

        What if your server fly over france , but not in France, hence: you don't need to build servers in france, unlike before, you don't need to deal with local government on so many issues, water, electricity etc to be local in france.

        And , taxes : crypto payments + compute , and same transaction in france doesn't have to be taxed anymore :)

        Yes, you have to pay taxes to US government, but not to france.

        • And if France decides to jam you until you play nice?
          • it's extreemly hard to jam starlink, ask russians at war. also that gpu run results can be connected somewhere in england, and requested using ipv6 e.g. you need to start moderating internet heavily etc.
  • It's fun to debate this and all, but the reality is that datacenters in space are going to happen, and soon - maybe even this year. If we've come this far, then there's already a viable plan that we just don't know about yet.
  • The top comment: "Musk is up to something here."

    It never fails here. Ya'll are soooo determined to assume ulterior motivations. He has always been direct about his motivations, whether it's about politics or business decisions.

    To suspect his whole plan for datacenters in space is a ruse or something to drive up some stock price (or whatever), is... just ridiculous. You really think they person who leads SpaceX (more satellites than the rest of the world combined) and Xai (with a competitive frontier model in 2 years starting from scratch), and Tesla (more inference compute than any company on Earth) really knows less than you about the math and physics of this idea??

    His immediate focus for Starship has shifted from Mars colonisation to exponential expansion of intelligence, as he thinks it's the best path to extend consciousness. Ridiculous or not, he believes that, and that's the motivation.

  • ViT (Vision Transformer) fine-tuned on a Starcloud satellite in space (using the Flower framework) -- to the best of our knowledge, this is a world first: https://flower.ai/blog/2026-02-02-flower-labs-and-starcloud-...
  • It's not supposed to make sense. It's supposed to be cool and signal that demand for the stock will not go down.
  • Consider: If you genuinely believe that the only important goal is to make life multiplanetary, (and note I'm not defending this position here, just asserting it as an explanation of behavior)

    then anything that drives money towards your work on that goal is worth pursuing particularly if you think time is short.

  • > Data centers in space only make sense if they are cost effective relative to normal data centers.

    This statement is actually completely false. The bottleneck is not cost of building data centers, but the energy accessible on the planet. How much we're willing to pay for increasing that is currently very unclear, but it's far more than the current cost of building a terrestrial data center.

    As Jensen Huang famously touted their performance per watt, saying "Our customers won't buy our competitor's chips even if they were free."

    • > This statement is actually completely false. The bottleneck is not cost of building data centers, but the energy accessible on the planet.

      How much of energy will it take to launch the same amount of compute, connectivity, and PV to power it into space?

  • Heat energy shedding is often talked about as an Achilles Heal of orbital computation.

    But heat radiation rates are proportional to temperature to the 4th power!!!!

    That is a magical law. The quality of heat pumps used to concentrate heat, will drive the economics and structure of heat dissipation.

    Seldom do we get constraints that favorable to work with.

  • Elon has used the greater fool theory for so long that they no longer exist on earth (at least fools with money who aren't also using the greater fool theory). It makes perfect sense he would focus on space because if he does find aliens it'll be an entirely new investor pool for him, and he desperately needs that now.
  • I was listening to a podcast featuring Gavin Baker and he went on and on about models being defined in generations, and we will be moving from Blackwell generation to Rubin generation soon and it will be awesome. This is not something I know a lot about and he sounds like an expert I could learn so much from.

    Then he talked about datacenters in space and this is something I have some appreciation for, and I immediately knew he couldnt have done much Physics, and sure enough, I was right.

    There are "experts" out there who basically have no idea what they are talking about, "it is absolute zero in space in the shadow!", as though radiative cooling is that effective.

    And that's not even talking about part failures. How do we replace failed parts in space? This is a scam, but everybody is afraid to openly challenge eloquent "experts" who are confidently wrong.

  • Cool! If there are people working on something, despite others saying "it makes no sense" I assume it's a hard and interesting enough problem.
  • Ground-based data centers will always be cheaper. There is no advantage in space that makes it worth spending more.
  • I always thought that in the case of a rouge AI breakout that we could just cut the power or network. This makes both impossible. The sick genius of SkyNet was having the most defensible infrastructure when it became clear that whoever controls the biggest robot army can take out enemy data centers and control the world. Now I hope that shooting down LEO satellites is cheap and DIY-able.

    I think it’s all farce and technically unsound, but I also think that grok-5-elononly is a helluva drug. It’s really got him ready to rally investors behind “spreading the light of consciousness to the universe”. Oh to see the chat logs of their (Elon and his machine girlfriend)’s machinations.

  • > Data centers in space only make sense if they are cost effective relative to normal data centers.

    Author made a fatal mistake. By flying enough hardware in space, you can simply blot out the sun and steal their solar capacity. Drink their milkshake with a long straw!

  • The worst thing about this isn't that it makes no sense. It's that it doesn't even _try_ to make sense.

    These companies wanted to merge for financial reasons and the invented reason is nonsensical. We shouldn't even give the nonsensical reason the benefit of trying to make sense of it.

  • Feels like this is about as unserious as flamethrowers, the Boring Company, and Hyperloop.

    We're living in the Age of Distraction… amusing ourselves to death (as usual).

  • Thinking of power infra. Even solar. Doesn't that last 20 or 30 years at least? With some maintenance, but before full overhaul. So in space you would probably decommission it at same time right? Wouldn't that be additional cost?
  • Just like an idea of using an oil-powered carriage instead of a good'ol horsie was in 1910.

    Listen, I totally agree, the tech makes absolutely no sense. It does not. But the fact that someone is willing to spend money on figuring this out is pretty good. The worst thing is going to happen, we'll have a cheaper space travel. And let the guys to have the first hit at it, wasting money on an enormous amount of research needed.

    Ain't my money being spent.

    As long as we don't have to use Russian rockets to send the US payload to the orbit, I'm cool with it.

    • It is your money being spent. ~40B so far. Though half of that is for services.

      But more abstractly, it's our resources that are being allocated. The planet as a unit is deciding where to put it's effort. Apparently we're not very good at this

    • I can’t take any of it seriously.
  • heat dissipation is one thing - another is the recycling - anything he shoots into the orbit will essentially be disposable, single use DCs. Once they fail, it will be just a dangerous junk waiting to be deorbited. And all the precious materials which normally get recycled will be lost....
  • Space - no. Moon - yes

    Space is cold but has little mass. Either heat can radiated or transfered. To transfer heat, mass which easily absorbs heat is required. The moon might be suitable for that.

  • Current analysis shows space-based compute costs roughly 3x more per watt than terrestrial equivalents, requiring launch costs to fall below $200/kg before achieving economic parity—a threshold unlikely before the mid-2030s even with Starship’s full reusability.

    While technically not impossible, the space data center vision appears primarily designed to support SpaceX’s anticipated mid-2026 IPO and justify a $1.5 trillion valuation rather than solve near-term compute constraints.

  • > Ground-based solar panels have been getting more cost effective for decades and show no sign of slowing down.

    I'm no expert on solar but I thought there was some upper limit on how much power ground-based solar panels can generate per area based on how much energy gets through the atmosphere all the way to ground - and that panel efficiency was approaching that limit.

    However, I don't doubt ground-based panels can continue to improve in cost and other metrics and thus exert competitive pressure on space-based solutions.

    • People are gettingtoo hung up on the radiator math and completely missing the massive input advantage of AM0 versus AM1.5. On Earth you get around 1,000 Watts/m^2 (ideal), but in realtiy shave off 20–25% because of clouds and night time. In a sun-synchronous orbit, you’re pulling close to 1300 W/m^2, and that's 24x7. That is easily a 5x to 6x energy yield advantage per square meter of panel per day, and when you have that much surplus energy free from the vacuum, you can afford to brute-force the cooling problem by dumping massive wattage into active heat pumps to raise your radiator temps, effectively paying for the inefficiency of space cooling with the abundance of space power.
      • You do not solve a problem that is many orders of magnitude more difficult with a mere 5x to 6x efficiency gain.
    • Requirements for power still don't come close to total or practical surface area. If we get to that point, space collectors with microwave beams to the ground are viable.
  • Computing hardware that isn't rad-hard is going to have a bad time without a handy atmosphere for shielding.

    And hardware that is happy in high-radiation environments is not going to be fast.

  • > Kessler syndrome: a cascading explosion of debris crippling our access to space

    I'm taking the parts of this write-up I don't have expertise with a grain of salt after seeig this.

    Kessler cascades are real. Particularly at high altitudes. They're less of a problem in LEO. And in no case can they "[cripple] our access to space." (At current technology levels. To cripple access to space you need to vaporise material fractions of the Earth's crust into orbit.)

    • Yep. I'm no fan of Elon - exactly the opposite, in fact - but this is just someone trying to look smart and eco-friendly by doing the simplest, least ambitious, most obvious and surface-level analysis.

      The sentence you mention was indeed a give away, but there are many others. Worst case scenario, nothing works and Elon burns a bunch of money, part of which goes into jobs and research. Best case scenario, we actually move away from technologies from the 50's and end up with daily, cheap earth-to-low-orbit (ideally something better than that - how about the moon?), no more whining about energy costs, and laser communication IRL. That's just the obvious stuff.

      Being "realistic" and "having a budget" is what companies like Google do. That's all good, but we have enough of those already.

    • SpaceX made a request of the FCC to authorize a constellation of 1 million satellites. And these are going to be much larger, "data center" satellites. This many satellites, all in the same orbit (sun-synchronous is a specific orbit), vastly changes the math on Kessler syndrome.
    • > Particularly at high altitudes.

      Well, maybe "higher", but not really high.

      The lower the altitude, the larger the odds of making one, in a quadratic fashion. But also the lower the altitude, the less time it will last.

      There is some space where it lasts basically forever but is small enough for it to happen. It's higher than LEO, and way lower than things like GEO.

  • This blog post has some sliders you can tweak to see if you can make the numbers make sense: https://andrewmccalip.com/space-datacenters

    "So here's what I did. I built a simple model that reduces the debate to one parameter: cost per watt of usable power for compute. The infographic below lets you change the assumptions directly. If you disagree with the inputs, great. Move the sliders. But at least we'll be arguing over numbers that map to reality.

    The model is deliberately boring. No secret sauce. Just publicly available numbers and first-principles physics: solar flux, cell efficiency, radiator performance, launch cost, hardware mass, and a terrestrial benchmark that represents the real alternative: a tilt-wall datacenter sitting on top of cheap power. "

    "Here's the headline result: it's not obviously stupid, and it's not a sure thing. It's actually more reasonable than my intuition thought! If you run the numbers honestly, the physics doesn't immediately kill it, but the economics are savage. It only gets within striking distance under aggressive assumptions, and the list of organizations positioned to even try that is basically one."

  • typ
    Assuming that we place an iron ball (ideal sphere-shaped and thermal conductivity) on the SSO (solar synchronous orbit), how hot can the object be?

    Given the solar constant 1361 W/m^2, you can calculate the temperature range based on the emissivity and absorptivity. With the right shape and “color”, the equilibrium temperature can be cooler than most people thought.

    I suppose that a space data center powered 100% by solar is no different than this iron ball in principle.

    • The ideal shape would be a shaded, flat panel perpendicular to the sun right?
      • That should be better than a sphere. Though I imagine there could be some fancier 3D geometry designs.

        Even for a simple sphere, if we give it different surface roughnesses on the sun-facing side and the "night" side, it can have dramatically different emissivity.

    • About 120 degC.
  • It doesn't make any sense to me either, but there are lots of things like that where the other thing is harder. As an example, a thing people say online a lot is something like "Why do the techbros build self-driving cars instead of just putting it on rails for efficiency and then they could call it a TRAIN?"

    The answer to that is that coordination problems are really hard. Much harder even than what are currently unsolved engineering problems. In fact, SpaceX can only launch from California because they have DOD coverage for their launches. Otherwise the California Coastal Commission et al. would have blocked them entirely. Perhaps the innovation for affordable space Internet is combining it with mixed-use technology.

    The truth is that in America today self-driving cars (regulated by a state board run by bureaucrats) are easier to build than trains (regulated by every property owner on the train route). Mark Zuckerberg tried to spend some money evaluating a train across the Bay and had to give up. But Robotaxi service is live in San Francisco.

    So if there is an angle that makes sense to me it's that they anticipate engineering challenges beatable in a way where regulatory challenges are not.

    • Interesting insight. I can think of some objections, but they don't change your point.

      I also checked out your blog and got 2 interesting articles in 2 tries. If you have some personal favourites and listing them is not a bother, I'd be happy to read them.

  • What data centers in space enable is protection for the compute of near-superintelligent AIs from the interference of humans.

    As an alleged human, I'd like to preserve my option to interfere.

    • No, no, no - Villa Starlight was the prison the Tessier-Ashpool AI needed help to escape from!
  • No, but protecting x/xAI from bankruptcy by linking it to the most promising company in Musk's portfolio does. You just need a justification.

    This is while they try to find a solution to earn money with it.

  • > Training and serving frontier AI at scale takes hundreds of thousands of GPUs. xAI’s Colossus cluster reportedly has 200,000 GPUs. OpenAI has plans for millions of them. Competing in this market would require launching hundreds of thousands, if not millions, of satellites into space

    No? You'd only need one with lots of gpus on the ship at the same time

  • I don’t know, it probably would have been useful if Cyberdyne Systems had developed its AI in space?
  • Data centers in space have one advantage: FBIs can't physically raid them.
  • Reasonably sure this has less to do with putting data centres in space and more to do with getting them less auditable (see the other news about X getting raided about Grok)
  • Isn't Starlink already basically a distributed datacenter in space? they have like ~9k+ satellites up there already at least according to: https://planet4589.org/space/con/star/stats.html.

    what am I missing here?

    • I'd assume Starlink satellites do the minimal possible amount of compute required (thus power used, thus heat generated) to provide service. The builders of data centers are hungry for as many watts on Earth as they can source.
  • How much of this is because putting data centers in space is WAY harder for any terrestrial government to get their hands on and seize or block?

    They make no sense otherwise.

    The only other thing I can think of is the whole thing is just a scheme to get investment and they’re never going to actually go through with it.

    At this point I kind of think the former is more likely.

  • You might want some compute in space that you know is very hard to physically interfere with.

    But general purpose compute no

  • Data centers in space make sense because its nigh impossible to build things terrestrially. NIMBYism is so out of control the largest solar array in the US in the middle of the mojave got cancelled because it would interfere with the view.

    "Just change the law" ok sure we'll get right on it.

  • Electric cars make no sense.

    Reusable rockets make no sense.

    Autonomous cars make no sense.

    Data centers in space make no sense. <--- You are here.

    Humanoid robots make no sense.

    • Hyperloop: makes no sense

      Solar roof tiles: makes no sense

      Lot's of tiny tunnels under cities: makes no sense

      Performance of the new roadster: makes no sense

      All four of the above were likely scams. Musk is not beyond running a scam.

    • Cherry picking makes no sense.
  • I guess the xAI/SpaceX thing is mainly a financial move and they made up an interesting story to give it some context
  • AST Spacemobile is successfully deploying cell towers in space; to compete with Elons Starlink. Not to mention ASTS is collaborating with American Tower, Google, ATT, Verizon, Nokia, and other big dogs for this venture. Now a DC is magnitudes different then a cell tower/satellite but hey .. if the RoI is there, it can be done
  • This only makes sense if it somehow helps to evade some kind of regulation. I'm not quite sure which though.
  • Data centers on earth don't make sense either.
  • I agree with the author and the bit about xAI and investors makes sense. But why does a company like Google invest in this ridiculous idea?
  • Data centers in space make perfect sense, in exactly the same way as a jetpack made perfect sense. It is an excellent vehicle to ride out some juicy government contracts for as long as you can keep the grift going.

    https://pluralistic.net/2024/05/17/fake-it-until-you-dont-ma...

  • We really need to stop letting Musk and others just put what ever they want in space we are getting close to the Kessler limit and that could be very very bad if it happens. They have some ideas but this is already and issue, China had an issue after a launch were debris hit the capsule breaking it forcing them to send a second capsule.

    https://climatecosmos.com/sustainability/how-close-are-we-to...

  • I bet they can already weaponize their satellites to prevent the launch of other satellites.

    Putting data centers in space keeps them out of reach of humans with crowbars and hammers, which may have been a vulnerability for those robots Tesla is building.

  • But data centers in the sea...
  • That's the point. Nonsensical ideas (like humans on mars) drive valuations higher. There is not even a point to argue about practical matters.
  • Google, Spacex, several startups are all doing this. The best people in their fields think it might be viable. I'm skeptical as well, but you do wonder if maybe they are right and how exciting that would be.
    • Everyone else is announcing initiatives to investigate the feasibility of this because earthlings currently hate the data center build out. The news is full of anti-DC stories about how much electricity/water they're using. They're selling a story.
  • I don't get the point at all of these. You:

    - have very non-deterministic latency

    - are located outside of a country that can protect you (ie China could disrupt your space data center)

    - have to pay millions of dollars to swap out hardware

    • And what about servicing? Last I checked these data centers don't run without incident and need people (or fine robots) to physically interact with them.
    • You’re also located outside of any country that could regulate
      • A country will definitely still be able to regulate you. Also under what regulations they'd be afraid of other than local building laws
    • and : kessler syndrome
  • I feel like he has no intention of implementing this. It's all just justification for it to not hit up against an regulatory objections to combining the companies.
  • Given xAI's gross disregard for environmental regulations in building Colossus, the reason for building datacenters in space seems obvious: there's no EPA in space.
  • After the hyperloop fiasco I don't understand why anyone gives Musk any credibility at all
  • Remember what the Luddites actually did? They sabotaged the machines that were disrupting their livelihoods. If AI is as disruptive to large numbers of workers as some people think it will be, keep in mind it's a lot easier to destroy a GPU that's stored on earth than one in space.

    Anyone planning expenditures as large as a modern data center thinks about all kinds of risks (earthquakes, climate, power, etc), and so perhaps there is a premium for GPUs that are out of the reach of your median angry unemployed guy.

    (yes, this is nuts, but I can easily imagine some fever-dream pitch meeting where Musk is talking about it)

    • The luddites won't need to sabotage a space based GPU. They can just wait for waste heat, radiation, or a good old solar storm to do it for them. The rest of the ground lauch infrastructure is fragile.
  • Whatever it is it’s not driven by sense or even feasibility of data centers in space.

    To me it looks like the next Musk’s grift. Remember Mars? Have you heard about it recently? He threw it to the Internet and everyone got excited for a minute. Then nerds did quick math and it didn’t make any sense. And so everyone forgot about Mars. This is the same. Hype everyone up for a week or two to inflate stock before the merger/purchase/IPO/whatever. That is all.

    • Exactly, Musk is just playing pump and dump with industrial projects.
  • This is when you know we reached peak AI. Data centers in space talk.
  • Is there any insight into how Starlink solved cooling? One 'expert' insisted that there is no reason to expect that data center satellites would generate any more heat than starlinks.
    • Those have a power budget of about 1 rack. I would expect a datacenter satellite to need more cooling if it has more compute.
      • And 1 ML rack uses the power of like 10 regular racks
        • Oh and even a non-ML server rack uses more power than a networking rack
    • So, most of the power that Starlink satellites use go into the comms, right? Blasting out electromagnetic radiation to receiver stations on earth, and also the laser(?) backhaul between satellites.

      Modulo some efficiency losses, most of the electricity it generates is leaving the satellite. Contrast with a datacenter, where most of the energy is spent heating up the chips, and the rest is spent moving the heat away from those chips.

  • It's not supposed to make sense when you're screening for supporters who will believe anything you say.
  • The bigger issue: datacenters in space are disposable. All the extremely recyclable aluminum, silica - you extract it, manufacture it and instead of recycling it when it’s done you incinerate it in the atmosphere and scatter the ashes far and wide across the earth, the harder to recapture later.

    You do this when the most fragile part in the system fails. Solar panels good for 25 years but the SSDs burn out after 2? Incinerate the lot!

    This kind of thinking is late capitalist brain rot. This kind of waste should be a crime.

    • Aluminum is 8% of the earth's crust and silicon is 28%; I think we're good
  • It sounds cool and gets investors.
  • What jurisdiction does a data center in space fall under, anyway? The one of the nation that launched it?
  • you know you're looking at some hard analysis when they use the number "gazillion". can I get that one in scientific notation?
  • Keep talking like that and people will colonize space
  • I’m surprised everyone is worried about heat dissipation.

    Datacenters in space is ambiguous enough to mean on lunar soil which provides plenty of heat dissipation using geothermal heat pumps.

    Similarly mass to orbit is also less problematic if silicon factories (including the refineries) are built on lunar soil as well.

    • They have filed actual plans with the FCC for their satellite constellation. They are not talking about lunar data centers.
  • Let's do some napkin math on it

    Current satellites get around 150W/kg from solar panels. Cost of launching 1kg to space is ~$2000, so we're at $13.3(3)/Watt, that just power, let's assume that cooling will cost us same per kg, the same amount need to be dissipated so let's round it to $27

    One NVidia GB200 rack is ~120kW. To just power it, you need to send $3 240 000 worth of payload into space. Then you need to send additional $3 106 000 (rack of them is 1553kg) worth of servers. Plus some extra for piping. We're already at $6.3 mil a pop for just hauling it up to orbit, with no cost of solar cells included

    I'd imagine comparable hardware for just some solar + batteries on ground is around $200k. I dunno where the repeated 5x cost number comes from. I suspect whoever pushed it was just lying

  • I thought chips need to be radiation-hardened to work in space.
  • where do you put things, so that no one will be able to warrant thier way into access?

    entirely out of jurisdiction, where it is prohibitively expensive to travel, and impractical for any physical seizure.

    you dont need to compute, just store it and P2P amongst satellites.

    essentially an orbital NAS.

  • Three counterpoints:

    1) Kessler syndrome is a contingency.

    2) This is a logistics issue, not a physical impossibility.

    3) Those are different tradeoffs (solar in space). There is not really an argument there.

    All in all this is extremely weak reasoning, which is quite the contrast with the definitive title.

    I throw this to the "nerds need to feel smarter than Elon" pile of articles. :)

  • prompt: what's the term for financial moves where you keep finding new investors to pay off the previous ones

    GPT-4o mini: The term for financial moves where new investors are continually recruited to pay off previous ones is often referred to as a "Ponzi scheme." Another similar term is "pyramid scheme," where returns are paid to earlier investors from the contributions of newer investors, but with a structure that typically requires participants to recruit others to earn returns. Both schemes are unsustainable and illegal.

  • You’re missing one important point: radiated power scales with the fourth power of temperature. Could it be that xAI has a chip capable of operating at very high temperatures?
  • Two reasons why it makes sense (really really good reasons):

    1) Water scarcity and energy scarcity here on earth

    2) It will drive down launch costs and promotes investment in orbital facilities and launch capabilities.

    those two reasons alone are enough.

    • What does water scarcity have to do with anything? Data centers don't use water. They slightly heat it, and then it flows back out to whatever it would have done anyway.
      • They need fresh water which is scarce unlike salt water, once they use it, it can't be used for anything else. They're competing with water supplies of municipalities these days. Not a big deal if you're near the great lakes or the missisipi, but a big deal in california, arizona, utah,etc.. and that's just the US. There are places that are becoming unlivable because of water supply issues, and datacenters are needing to be built near them.
        • > once they use it, it can't be used for anything else

          This is not true!

  • This makes the same amount of sense as colonising Mars.
  • There are two very distinct kinds of AI workloads that go into data centres:

        1. Inference
        2. Training
    
    Inference just might be doable in space because it is "embarrassingly parallel" and can be deployed as a swarm of thousands of satellites, each carrying the equivalent of a single compute node with 8x GPUs. The inputs and outputs are just text, which is low bandwidth. The model parameters only need to be uploaded a few times a year, if that. Not much storage is required , just a bit of flash for the model, caching, logging, and the like. This is very similar to a Starlink satellites, just with bigger solar panels and some additional radiative cooling. Realistically, a spacecraft like this would use inference-optimised chips, not power-hungry general purpose NVIDIA GPUs, LPDDR5 instead of HBM, etc...

    Training is a whole other ballgame. It is parallelisable, sure, but only through heroic efforts involving fantastically expensive network switches with petabits of aggregated bandwidth. It also needs more general-purpose GPUs, access to petabytes of data, etc. The name of the game here is to bring a hundred thousand or more GPUs into close proximity and connect them with a terabit or more per GPU to exchange data. This cannot be put into orbit with any near-future technologies! It would be a giant satellite with square kilometers of solar and cooling panels. It would certainly get hit sooner or later by space debris, not to mention the hazard it poses to other satellites.

    The problem with putting inference-only into space is that training still needs to go somewhere, and current AI data centres are pulling double-duty: they're usable for both training and inference, or any mix of the two. The greatest challenge is that a training bleeding edge model needs the biggest possible clusters (approaching a million GPUs!) in one place, and that is the problem -- few places in the world can provide the ~gigawatt of power to light up something that big. Again, the problem here is that training workloads can't be spread out.

    Space solves the "wrong" problem! We can distribute inference to thousands of datacentre locations here on Earth, each needs just hundreds of kilowatts. That's no problem.

    It's the giaaaant clusters everyone is trying to build that are the problem.

  • It’s less about putting compute in space as occupying that space before anyone else does. For any reason: spying, space warfare, network and communication.

    First mover advantage, and all.

  • The whole premise misses the point, that earth is somehow in the very same space too.

    Adding a global UHVDC grid to even out dips in local PV performance due to cloud cover and the diurnal cycle on spaceship earth seems to be magnitudes cheaper and scaleable than this loony pitch.

    The only thing making this hard is requiring supranational collaboration.

  • Like there isn’t enough stuff floating up there already.
  • I get it. This is a scam. The discussion is not about what you think it is. (EDIT: Or not, I don't care.)

    BUT the fact that we are even arguing about whether or not we should be putting data centers into space is so incredibly absurd to someone who watched the Challenger explode and assumed that space wouldn't be ventured into again in my lifetime.

    People don't realize how much the priors have changed. Take a minute to appreciate that. We are living in a world where people are debating if it makes sense to spend a bazillion dollars to put a hard disk into orbit.

    I wonder if the Klingons are good at cyber warfare.

    • The problem is that software people are clueless.
  • You can debate this until you are blue in the face. If the costs are less they will do it. If they aren’t they won’t do it. That’s the only sense that needs to be made.
    • Ah, yes, the "efficient market hypothesis", it's well known that no company has ever gone bankrupt because every company only does things that are optimally efficient and profitable.

      No company has ever made an investment in something that ended up being more expensive than calculated, or so expensive it bankrupted them.

      • You are assuming they will commit to the solution and ride it to their grave trying to make it work. They will experiment and figure out a way to make it cheaper, or they will give up. They have plenty of money to experiment with this.
  • With all that great tech to land and reuse rockets, they still need to be propelled into space using... kerosene. That's right. 1 million satellites launched into orbit using kerosene.

    Does not feel like a vibe.

  • hello,

    as always: imho. (!)

    we already had this topic before, an example for another good article regarding physical arguments against this idea would be:

    "Datacenters in space are a terrible, horrible, no good idea" ~ late 2025

    * https://taranis.ie/datacenters-in-space-are-a-terrible-horri...

    TL;DR: It's not going to work.

    idk ... maybe elon has something else in mind with this merger!?

    cheers,

    a..z

  • Don't let common sense stop you from a good time.
  • It seems quite telling we are even discussing this.
  • "So if this is clearly nonsense, why are serious companies and investors piling into it?"

    What does "serious" mean

  • The French government issued a child porn warrant for the CEO and it isn't even a topic for discussion. That's what doesn't make sense to me. It's silly to talk about solar panel prices like reality matters at all to his cult of followers. It doesn't have to make sense. The less sense the better.
    • It's not a warrant, it is a summon for interview. That's actually very different: the way you phrased it suggests that there is a warrant for his arrest (mandat d'arrêt)...
  • I'm glad I read HN.

    My take-away is - SpaceX is still an extremely good stock to hold. However, the stupid money will buy the stock at IPO on the promise of space datacentres.

    When SpaceX inevitably u-turns on this plan and the stock plummets temporarily, THAT will be a good time to buy in.

  • Can't wait for competitors destroying the other guys installation because just like international waters, there is no police or border there.
  • Clearly the desire to have data centers in space is so that AI can control humans remotely without having to worry about backlash and potential dismantling.

    Besides this, it's concerning how much stuff we're sending to space. One day we'll have to start worrying about satellite parts falling on us.

  • It makes sense if you want to avoid tax. You can put artificial costs and deduct them. Nobody is going to go to space and check.
  • No no, let Musk cook. This definitely won't be SpaceX's Cybertruck moment, where they completely throw away their first-mover advantage by wasting five years chasing after the egotistical boondoggle of a delusional megalomaniac.
  • This being a forum full of engineers, it is not surprising that everyone concentrates on the technical challenges thereof. But that may be a distraction.

    I suspect that Musk wants to build space data centers in order to mitigate political and societal problems, which may yet prove more intractable than cooling in space.

    The current expansion of terrestrial data centers has already caused a huge backlash. Their adversaries may well try to regulate them out of existence, at least locally. If an important jurisdiction like California or Germany subjects building of new data centers to regulations similar to building, say, a new nuclear power station, they will achieve a de-facto stop on further development there even without banning them outright.

    Space, while not entirely lawless, is much harder to regulate this way. Local authorities have no power over it, nor do governments of nations without space capabilities. Big authorities of big nations (the FAA etc.) do, but they will likely be more friendly to already established launch businesses like SpaceX, not least because of the geopolitical dimensions of having a vibrant space sector.

    From Musk's POV, this may be worth the additional cost and technical troubles.

  • I am willing to bet the whole xAI/SpaceX merger is simply a ploy by Musk to evade releasing accurate historical information about SpaceX's finances. How much did it actually cost SpaceX to launch a kilogram of payload into space each year? How much is NASA actually donating them, per each year?

    I mean, I still remember promises of $1000-per-kg for space launches, and how e.g. Gigafactory will produce half of the world battery supply, and other non-scientific fiction peddled by Musk. Remember when SpaceX suggested in 2019 that the US Army could use its Starship rockets to transport troops and supplies across the planet in minutes? I do. By the way, have they finished testing Starship yet, is it ready?

  • It's lala land nonsense.

    - Data centres need a lot of power = giant vast solar panels

    - Data centres need a lot of cooling. That's some almighty heatsinks you're going need

    - They will need to be radiation-hardened to avoid memory corruption = even more mass

    - The hardware will be redundant in like 2 years tops and will need replacing to stay competitive

    - Data centres are about 100x bigger (not including solar panels and heat sinks) than the biggest thing we've ever put in space

    Tesla is losing market share (and rank increasingly poorly against alternatives), his robots are gonna fail, this datacentre ambition needs to break the laws of physics, grok/twitter is a fake news pedo-loving cesspit that's gonna be regulated into oblivion. Its only down from here on out.

    • Maybe instead of housing life, civilizations develop Dyson's spheres to house data centers. Solar panels on the interior, thermal radiators on the exterior and the data centers make up the structure in between. Combine that Von Neumann probes and you've got a fun new Fermi paradox hypothesis!
      • Don't combine it with von Neumann probes and you've solved the Fermi paradox: a civilization that puts that much work into computing power is either doing the equivalent of mining crypto and going nowhere, or is doing AI and is so dependent on it that they inevitably form a vast echo chamber (echo sphere?) that only wants to talk to itself (itselves?) and can't bear to be left out by adding the latency unavoidably added by distance.

        tl;dr: civilizations advanced enough to travel between stars end up trapped by the resources and physics required to keep up with the Joneses.

    • > - The hardware will be redundant in like 2 years tops and will need replacing to stay competitive

      Hey! It can be de-orbited onto the location of your choosing. I bet you can sell this service to the DoD!

      Barring that, you can sell it on the global market to the highest bidder.

  • Data centers on earth alone don't make sense if we want to expand further into the galaxy.
  • Elon announced this so he could troll the comments on HN and get all of this incredibly valuable armchair expertise in solving his problems.
  • If we won't stop what he is doing with grok and ai-generated CSAM, he will be completely free from oversight up there.
    • As silly as that sounds, you gave me a thought ...

      If SpaceX, by being a company serving the federal government are covered by a law that would make its offices (on Earth, duh) a protected area ... then could they by some law-bending make that protection also encompass the data centres that contain the AI-generated CSAM and training data, in order to protect them from being raided by state law enforcement?

      That does not have to sound reasonable to us ... only to Musk.

    • Dealing with rogue AI also seems easier when you can walk up to its data center and unplug it.
  • Eager Space [Orbital Data Centers Yes or No](https://www.youtube.com/watch?v=JAcR7kqOb3o) Goes into great detail with extensive calculations (for a YT video at least). TLDR: Cost to orbit needs to be under $200/kg before it makes sense.
  • Of course it makes sense. It's a cool story to pump up the valuation in the AI datacenter boom. This meme will keep on delivering until (if) the AI bubble bursts.
  • Admiral Grace Hopper is famous for using a length of wire to explain to others what a nanosecond was.

    https://www.pbs.org/newshour/world/pentagon-embraces-musks-g...

    Data centers in space make absolute sense when you want as close to real time analysis on all sorts of information. Would you rather have it make the round trip, via satellite to the states? Or are you going to build these things on the ground near a battlefield?

    Musk is selling a vision for a MASSIVE government contract to provide a service that no one else could hope to achieve. This is one of those projects where he can run up the budget and operating costs like Boeing, Northrup etc, because it has massive military applications.

  • Another thing that doesn't make sense about them is that DCs get a lot of out of physical locality. Caches become hot as different use case spin up and down during the day near their customers.

    If the nodes are spinning around the earth at orbital velocities, then all the benefits of physical locality are thrown out the window.

    • But apologists would say that putting the data centers in LEO would mean that latency to a client via a ground station wouldn't be much more than ~50 ms extra. At least LATAM and Africa would be getting a good deal out of it with better coverage.
  • "Data centers in space only make sense if they are cost effective"

    The author forgot to add that this is only true from the perspective of their own bias.

    To someone else it might make a lot of sense, e.g. someone who expects militant resistance to the "data centers" from the general public or some other actor that is highly unlikely to achieve space capabilities.

  • no, no, no, the key enabler to space datacenter is complete out-of-world computer 3D printers. You print entire 130nm, hell, even 130 micrometer GPUs and DDR2 VRAMs to go with, entirely on the Moon solely from Moon dusts, and shoot the complete satellites out into Earth LEO using maglev sleds. PUEs, opex, nothing matter because the Moon factory is self contained and don't interact with Earthian economy at all. The ssh key into the factory will be the source to free money to whoever holding it.

    Is that possible in our lifetime? I'd be optimistic about that. Can SpaceX pull that off? Space what? ...

  • how much latency would a minecraft server in space have?
    • With live migration it could be quite low, like 10 ms.
  • "Let him cook" makes so much sense here.
  • Comments full of EDS. Everyone is a rocket scientist in here also.
  • If someone had the tech to cool stuff in space, that is required for this to happen, they’d have tons of easier and more lucrative opportunities right now on Earth to become the new richest person.

    Where is the tech?

  • A pie in the sky
  • wrs
    Next up, the Boring Company gets imaginary contract for underground datacenters, is now valued at $500B.
    • Nah. They get contract for mining on Mars, valued north of $1T.
    • there was an article recently about a company wanting to put nuclear reactors at the bottom of very deep boreholes (like km deep).

      I thought that was actually quite interesting/practical, because if there is a problem, you can just bury the problem.

      not like tmi/fukushima/chernobyl

      • Interesting idea. 2km deep could work. I'm not sure how cooling or maintenance would work.

        Depth below surface | Typical temperature (°C) | Indicative cost to drill 1.2 m diameter hole

        500 m | 15–25 | $5–10 million

        1 km | 25–40 | $10–20 million

        2 km | 50–70 | $25–45 million

        3 km | 75–100 | $50–80 million

        4 km | 100–130 | $90–140 million

        5 km | 130–160 | $150–250 million

  • It makes a misleading argument about the price of solar panels falling. The cost of solar power installations has been flat for a decade because it's dominated by other costs.

    Also why talk about training not inference? That needs data centers too and could be what they're intending to do.

    So this post is clearly not an effort to objectively work out the feasibility but just a biased list of excuses to support the author's unsubstantiated opinion.

  • The article kind of ended all of a sudden without much of a conclusion… but as most people by now have realised once they heard of the merging of Musk and Musk, it sounds more likely just a way of shifting money to pay himself rather than to actually build anything he says.

    I’d even bet that when they do IPO, there will be ZERO mention of “space data centres” in the prospectus!

  • Of course it makes sense.

    The regulatory framework is getting more and more difficult for data centers.

    The options are move to countries with less of an uphill regulatory burden (UAE?), but this comes with other issues.

    Space it is.

  • Honestly, it is funny that people even seriously discuss this. I mean, now. It is such a blatant bullshit that you'd expect this time people would say "okay, now Musk went too far, nobody would buy into this". Yeah, I wish.
  • Data centers in space make sense when you want it to cost 200x more than on land, be unavailable for repairs and upgrades, and be either high latency or be out of commission during periods of darkness.
  • A more reasonable project would be repurposing portions of the ISS for a data center and using that as a POC for larger scale stations.
  • What if you just took some ketamine and tried again? Does it make sense?
  • I just purchased a sandwich I made from myself in a deal that values me a $1tn. I plan to make toasties in space.
  • He's going to do a DOGE (memecoin not government agency) equivalent over phones new satellite links to his SpaceX sats outside anyone national jurisdiction. Worth the possibility of taking over being the world's global currency unconnected from any/all government.
  • What is this website?

    The website insists that you let it record your voice in order to show you the dangers of AI. Is it trolling the visitor? https://civai.org/talk

  • But it's absolutely amazing hype and memevestors love it.
  • I'm not sure datacenters in space have to make suense to everyone, or from the perspective of earth.

    Taking a creative step back, perhaps datacenters in space support something with Mars?

    As much as that might not seem realistic, I also have to counterbalance it with operationalizing and commercializing SpaceX, Starlink and Tesla relatively quickly when so much stays at the R&D stage for so long.

  • This is written by someone that is not in aerospace that thinks terrestrially.

    Engineering is always a question of tradeoffs.

    Launch costs are dropping, and we’re still using inefficient rockets. Space elevators & space trains, among others, can drop this much more, the launch costs are still dropping, even using rockets, maybe we’ll never get to elevators & trains the costs will drop so low!

    Radiation shielding is not required for VLEO or LEO, and phenomenally more capable aerospace processors are near - hi Microchip Inc! There are many other radiation solutions coming, no doubt with nuclear power.

    Satellites can be upgraded at scale, though for many things, it does not make $ sense to upgrade them, but fuel , reaction wheels, solar panels, among other things do make $ sense to replace.

    Latency was technically solved in 1995 & 2001 with the first laser comms missions NASDA’s ETS-VI kiku-6 and ESA’s Artemis , and Laser crossbars for comms are common. A full laser TDRS no RF is not yet extant but soon. Earth to deepspace was just demonstrated by ESA.

    Cooling can be significantly improved due to lower launch costs, heat piping, RTGs, TEGs, and thermoradiative cells, not to mention sunside solar and darkside inline radiators

    Furthermore, it is very likely that as neuromorphics with superior SWaP emerge, we could see very different models of space based computation.

    Economic tradeoffs should drive many of these decisions as I’m not discussing the other applications of datacenter in space

    • > Cooling can be significantly improved due to lower launch costs, heat piping, RTGs, TEGs, and thermoradiative cells, not to mention sunside solar and darkside inline radiators

      You're saying they're going to steal the night? We'll see the sun in the day, radiative cooling for surveillance AI in the time formerly known as night?

      I'll confess that the numbers aren't nearly as bad as I'd thought. Apparently, you can dissipate 1MW at 100°C with a 17m diameter sphere at night. So it's like the size of a small house. It doesn't even glow. On the other hand, you need a lot of temperature differential to move the heat out fast enough, which means your TPUs are going to be hellishly hot.

      Though you'd probably only run it when it's in the sun and radiate in other directions, so you don't have to store the power in heavy batteries. You need a 56m diameter disk of solar panels to provide 1MW, don't forget that.

      (All figures were vibe calculated with Claude and are unchecked.)

  • I'd be curious to know simply how large the thermal radiator necessary to keep a typical GPU server cooled would be. Do they completely dwarf the server size? Can you do something with some esoteric material that is not particularly load-bearing but holds up well in space to get around some of these challenges?
  • Facts.

    Just do the basic thermal heat transfer math.

  • We were supposed to be on Mars right now, but I guess data centers in space are nice too. Kinda disappointed they aren't on the moon.
  • What? A pump and dump scheme? I am shocked I tell you, shocked
  • What if they diverted a decent sized asteroid into earth orbit and put the data center onto that? Could it be put into a sun-synchronous orbit, cover one side with solar cells, and use the backside of the asteroid itself for cooling?
  • I mean everything he does is so honest, rational and well thought out in detail, right?

    How's that full-self driving promised for decades working out?

    How's the destruction of USAID working out (oh you wouldn't know a million dead now)

    We already have a data-center in space, sort-of, here's how many radiation panels it has to deploy for just the heat produced from the small number of low-power computers

    * https://i.sstatic.net/cpIBo.jpg

    (ISS, all those white panels are thermal heat radiators)

  • This sound like a Musk "idea". click. Of course.
  • How else would you secure skynet against Sarah Connor?
  • AI in space makes no sense because the data center will be distributed and half of the time your processors will be waiting for data (if you are lucky). When they are working, you need to cool them down. When they finally heed the call of gravity, your vibe coders can see the vapor of their work in the sky and you throw the entire unit as a loss (might be a net positive for tax purposes).

    This is BS, everyone knows that this is BS, but because this is Elon, there are still people who don't call out the BS.

    It might be distraction, he might be delusional, he might be asking his investors to stop asking for profit by giving them shares from SpaceX, but this is not him discovering new physics.

  • Like I’ve always said love him or hate him Elon Musk is a SPACE OIL SALESMAN!
  • A thought experiment. Imagine that you had some magic way of getting all the electricity you wanted at the south pole, you had good internet connectivity, and the various treaties about the place weren't an issue for you. Would you want to build a data center there?

    Seems like a pretty obvious "no" to me. Loudoun County is a much better choice, just to pick one alternative. Antarctica is an awfully inhospitable place and running a data center there would be a nightmare.

    And yet it's way better than space. It's much easier to get to. Cooling is about a thousand times easier. The radiation environment is much more forgiving.

    This whole concept is baffling to me.

    (Incidentally, a similar thought experiment is useful when talking about colonizing Mars. Think about colonizing the south pole. Mars is a harsher environment in just about every way, so take the difficulties of colonizing the south pole and multiply them.)

  • I can assure this author: strapping a company that lights money on fire (today, maybe not tomorrow) to a cash flow enterprise makes the IPO harder, not easier, in the absence of credible plan. The market speculates, but it’s not being completely irrational. I’d actually be surprised if we didn’t have factories or data centers in space one day.
  • Truth doesn't matter.

    What matters is that investors and shareholders love to hear about future space data centers.

    Obligatory /s.

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  • Data centers in space are the logical progression from the multi trillion business of m2m and edge computing. It removes all physical limits to investment.
    • You mean physical reality
  • ozim
    *Data centers in space only make sense if they are cost effective relative to normal data centers*.

    Disagree there are bunch of scenarios where Data Centers in space make sense. Like nuclear annihilation and having vaults across the globe to communicate and get back lost information because ground data centers would be wiped out by EMP from blasts.

    • Has it occurred to anyone that you can put computers underground? In this apocalyptic scenario you are describing, how do you expect the ground based command and control infrastructure to survive? Satellites are 100% reliant on ground based operations. That is a hard requirement. And if you put the command and control underground, might as well just skip the whole space based plan and just put the data underground.
      • Why is it hard requirement?

        You can make some part of operations on high orbit that won’t decay as much then more ops on lower orbits that decay faster.

        If you put stuff underground it is much harder to communicate.

      • And here I thought Musk's fans are all about digging holes in the ground. The flamethrower fumes might have caused temporary amnesia.
        • To say so I am not a Musk fan - I am sci-fi fan and I make imaginary/silly stuff up on my own.

          I also like reading how people argue with not what I wrote but with what they imagined I wrote.

          • It was not my intention to single you out, my apologies.

            There is nothing wrong to imagine anything you like. But if you do it as a CEO, i personally consider that as fraud. Guess I'm weird and old-fashioned like that.

    • In that case wouldn't space also get wiped by EMP? Seems like disabling satellites would be good move if you have a few nukes to spare.
    • After the bulk of humanity is wiped out, it will be a comfort that I can still use AI to generate dank memes.
  • Counterpoint: https://x.com/CJHandmer/status/1997906033168330816

    (If you can't xcancel it yourself your hacker card is revoked.)

    • That post does not appear to address or acknowledge any of these problems: 1) thermal management in space, 2) radiation degrading the onboard silicon, 3) you can’t upgrade data centers in orbit
    • This is not a counterpoint, it is a post discussing the same topic but it doesn't address any of the points in this article.
  • Space offers some unique benefits that enable computing that’s impossible or very hard to do on earth. E.g. Super conducting computing is possible, which can be thousands times to millions times faster than current CPU while using very little energy. When the satellite moves in the shade of the earth, temperature drops significantly. It can be low enough to enable superconducting. When the satellite moves under the sun, the solar panel can start charging up the battery to power the ongoing operation.
    • i don't understand? you won't insulate the craft from the sun? and you expect the craft to get rid of its heat just from being behind the earth for a moment?
      • When did I say no insulation? If it took only one moment for the satellite to fly by behind the whole earth, its speed is so great that it would be flung out of the solar system.
  • When an invention has not been made before it’s usually because people are lacking an insight that the inventors have.

    You can’t read a 300 word article in 1930 and know that a formula 1 engine could not be built.

  • What’s there not to like? Superconductors. Free electricity. No cooling necessary.

    Put those three together and maybe it’s possible to push physics to its limits. Faster networking, maybe 4x-5x capacity per unit compared to earth. Servicing is a pain, might be cheaper to just replace the hardware when a node goes bad.

    But it mainly makes sense to those who have the capability and can do it cheaply (compared to the rest). There’s only one company that I can think of and that is SpaceX. They are closing in on (or passed) 8,000 satellites. Vertical integration means their cost-base will always be less than any competitor.

    • > No cooling necessary.

      This is false, it's hard to cool things in space. Space (vacuum) is a very good insulator.

      3 are ways to cool things (lose energy):

        - Conduction
        - Convection
        - Radiation
      
      In space, only radiation works, and it's the least efficient of those 3 options.
      • > In space, only radiation works

        it's worse, incoming radiation also works to heat up objects that are in sunlight and in space. And you want to be in sunlight for the solar panels.

        This is why surface of the moon is at temperatures of -120C when it's night and +120C when it's day there.

        And the sun's radiation also flips bits.

        Yes, it's technically possible to work around all of these. There are existing designs for radiators in the shade of the solar panels. Radiation shielding and/or resistant hardware. It's just not even close to economic at datacentre scale.

      • Superconductors.
        • Magnets.

          (We're just saying random physics things right?)

          • Could we use a constant stream of micro-asteroids as a heatsink?
          • i think so, next is Quantum right?
          • No, just you. Superconductors don’t get hot. There is 0 resistance in superconducting mediums. Theoretically you could manufacture a lot of the electricity conducting medium out of a superconductor. Even the cheapest kind will superconduct in space (because it’s so cold).

            Radiation may be sufficient for the little heat that does get produced.

            • > Even the cheapest kind will superconduct in space (because it’s so cold).

              Space is not cold or hot - it isn't. It's a vacuum. Vacuum has no temperature, but objects in space reach temperatures set by radiative balance with their environment. This makes it difficult to get rid of heat. On earth heat can be dumped through phase change and discharged (evaporation), or convection or any number of other ways. In space the only way to get rid of heat is to radiate it away.

              Superconductors don't have any resistance - and so heating from resistance isn't present. However, no super conducting computers have been created.

              https://en.wikipedia.org/wiki/Superconducting_computing

              And yes, it is really impressive - but we're also talking about one chip in liquid helium on earth. One can speculate about the "what if we had..." but we don't. If you want to make up technologies I would suggest becoming a speculative fiction author.

              Heating of the spacecraft would get it on the warm side.

              https://www.amu.apus.edu/area-of-study/science/resources/why...

              > The same variations in temperature are observed in closer orbit around the Earth, such as at the altitudes that the International Space Station (ISS) occupies. Temperatures at the ISS range between 250° F in direct sunlight and -250° F in opposition to the Sun.

              > You might be surprised to learn that the average temperature outside the ISS is a mild 50° F or so. This average temperature is above the halfway point between the two temperature extremes because objects in orbit obviously spend more time in partial sunlight exposure than in complete opposition to the Sun.

              > The wild fluctuations of 500° F around the ISS are due to the fact that there is no insulation in space to regulate temperature changes. By contrast, temperatures on Earth’s surface don’t fluctuate more than a few degrees between day and night. Fortunately, we have an atmosphere and an ozone layer to insulate the Earth, protect it from the Sun’s most powerful radiation and maintain relatively consistent temperatures.

              If you want solar power, you've got to deal with the 250 °F (121 °C). This is far beyond the specification for super conducting materials. For that matter, even -250 °F (-156 °C = 116 K) is much warmer than the super conducting chip range of 10 K.

              Furthermore, the cryogenic material boils off in space quite significantly (I would suggest reading https://en.wikipedia.org/wiki/Orbital_propellant_depot#LEO_d... or https://spacexstock.com/orbital-refueling-bottlenecks-what-i... "Even minor heat exposure can cause fuel to boil off, increasing tank pressure and leading to fuel loss. Currently, the technology for keeping cryogenic fuels stable in space is limited to about 14 hours.") You are going to have significant problems trying to keep things at super conducting temperatures for a day, much less a month or a year.

              Even assuming that you can make a computer capable of doing AI training using super computers this decade (or even the next) ... zero resistance in the wire is not zero power consumption. That power consumption is again heat.

              ---

              > Theoretically you could manufacture a lot of the electricity conducting medium out of a superconductor.

              Theoretically you can do whatever you want and run it on nuclear fusion. Practically, the technologies that you are describing are not things that are viable on earth, much less to try to ship a ton of liquid helium into space (that's even harder than shipping a ton of liquid hydrogen - especially since harvesting it is non-trivial).

              ---

              Computing creates heat. Maxwell's demon taught us that doing 1 & 1 and getting one creates heat. Every bit of computation creates heat - superconductor or no. This is an inescapable fact of classical computation. "Ahh," you say " - but you can do quantum computation"... and yes, it may work... and if you can get a quantum computer with a kilobit of qbits into space, I will be very impressed.

              ---

              One of the things that damages superconductors is radiation. On earth we've got a nice atmosphere blocking the worst of it. Chips in space tend to be radiation hardened. The JWST is using a BAE RAD750. The 750 should be something that rings a bell in the mind of people... its a PPC 750 - the type in a Macintosh G3... running between 110 and 200 Mhz (that is not a typo, it is not Ghz but Mhz).

              High temperature super conductors (we're not dealing with the 10 kelvin but rather about 80 kelvin (still colder than -250 °F) are very sensitive to damage to their lattice. As they accumulate damage they become less superconductive and that causes problems when you've got a resistor heating up in the cryogenic computer.

              ---

              Your descriptions of the technology for superconducting computers is in the lab, at best decades from being something resembling science fact (much less a fact that you can lift into space).

            • Right. You build your computers out of superconductors, and they don't get hot.

              Sadly, they also don't compute.

              > Even the cheapest kind will superconduct in space (because it’s so cold).

              Is this a drinking game? Take a drink whenever someone claims that heat is not a problem because space is cold? Because I'm going to have alcohol poisoning soon.

              Let's see how cold you feel when you leave the Earth's shadow and the sun hits you.

            • If/when we get high-performance superconducting computers, we wouldn't need to put the computers in space in the first place.
            • You've invented a room-temperature superconducting material? No?

              Didn't think so.

              Currently available superconductors still need liquid nitrogen cooling, meaning they're not feasible for in-orbit installations.

    • Do you mean to suggest that computer hardware does not need to be cooled when it is in space? Or that it is trivial and easier to do this in space compared to on Earth? I don’t understand either claim, if so.
      • The computer hardware only needs to run enough AI compute to be smart enough to convince Musk that it's working. It should be fine.
      • Superconductors. Average temperature in space is around 4 K.
        • Even assuming that this la-la-land idea has merit, the equilibrium temperature at the Earth's orbit is 250 Kelvin (around -20C). The space around the Earth is _hot_.
          • There are people literally working on accomplishing this. I don’t understand what’s with the arrogance and skepticism.

            Edit: Not trying to single out the above commenter, just the general “air” around this in all the comments.

            I honestly believed folks on HN are generally more open minded. There’s a trillion dollar merger happening the sole basis of which is the topic of this article. One of those companies put 6-8,000 satellites to space on its own dime.

            It’s not a stretch, had they put 5 GPUs in each of those satellites, they would have had a 40,000 GPU datacenter in space.

            • The problem you are encountering is how you are discussing superconductors. If you want to convince people that they are relevant you should explain how they would be used. You haven't done that at all, you just keep repeating "superconductors".

              And it would be helpful if you showed some uses of superconductors in space similar to what you propose and not some vague proposal for research that would take decades to realize. I'm not familiar with any use of them relevant to this application and I take the other people responding to you are not either.

            • > There are people literally working on accomplishing this.

              They're reinventing physics? Wow! I guess they'll just use Grok AI to fake the launch videos. Should be good enough for the MVP.

              For the superconductivity idea to work, the entire datacenter needs to be shielded both from sunlight and earthlight. This means a GINORMOUS sun shield to provide the required shadow. But wait, the datacenter will orbit the Earth, so it also will need to rotate constantly to keep itself in the shadow! Good luck with station-keeping.

              There's a reason the Webb Telescope (which is kept at a balmy 50K) had to be moved to a Sun-Earth Lagrange point. Or why previous infrared telescopes used slowly evaporating liquid helium for cooling.

              > I don’t understand what’s with the arrogance and skepticism.

              Because it's a fundamentally stupid idea. Stupid ideas should be laughed out.

              I'm not talking about "stupid because it's hard to do" but "stupid because of fundamental physical limitations".

        • you do know about the Sun? Earth? and the Moon? where would you get this 4 kelvin?
    • Why is there no cooling necessary?
      • Space is cold - 4 K. Superconductors.
        • Repeating the word "superconductor" does not convince anyone of anything.
          • I don’t care about convincing anyone. A question was asked and I answered the best I could with the time I had at hand.

            Also read by comment above that discusses WHY superconductors could be the key to cooler electronics in space.

        • Space is not cold. Space is not hot either. Temperature is a property of matter. Empty space does not have a temperature. It is also a perfect insulator for conduction and convection, and as for radiation: it's a problem because of the sun heating up objects via its radiation.

          This is the basics, I'm not an expert. But I don't think that you have anything useful at all to say here.

    • Do you know the lifespan of those satellites? Do you know how many of those fall out (sorry, de-orbited) of space every year?

      Do you know the cost of sending up a payload of them?

      Do you know how much $$ you need to extract from those payloads to make the cost of sending them up make sense?

      Do you know how much they've lied about Starlink revenue and subscription counts?

    • Your exuberance for this topic is only matched by your lack of understanding about it.
  • After looking for a top level comment pointing to why instead of how, I logged in just for this as I could not find one. Extremely bullish on this move, let me try to explain.

    As most engineers realize right away, it is not going to be profitable to operate a regular datacenter in space, per the article (and I agree), so something else is going on here. Almost all the discussion is about feasibility, which is not by itself going to explain the situation.

    It is clearly somewhat feasible to build Starlink level infrastructure and operate it profitably. I would posit that the narrative is a funding vehicle for a more conservative, incremental objective.

    The very fact that the infrastructure is in space places the datacenter on the legal and geopolitical high ground. It's hard to raid servers if they are in orbit. It's hard to disable, audit, or arm-wrestle into submission. It doesn't have to have the scale we've come to expect in 2026 to be useful. And it's for inference, not training, of course. Useful levels of inference is computationally cheap. There are implications with the financial system as well.

    In combination with PLTR technology, what I see is another intelligent and strategic move by Musk to enable and be part of hegemony. He is a central player not making decisions in isolation. They are playing a game with different rules, and therefore different unit economics.