- I fear this is only the start of it. A minimum of 3-4 constellations more will probably be launched in the near future (Russia, China, EU).
Their obvious dual-use nature makes them tempting, and a military target if a large conflict will take place in the near future. I hope their lower orbit will help any space junk burn up fast.
- If you blow up a satellite, half of it will end up going slower and half will go faster. The slower bits will probably burn up nicely, but the faster bits will just elevate their orbit.
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- Why are satellite trails not continuous lines
Is the camera exposure taking a few seconds of break between takes that get stacked later with some "missing" moments in between?
- Passing clouds?
- I've taken long exposures using film (analog, so no stacking or any other funny business) and saw the same thing. I always thought they were planes but now it seems they may have been satellites. I'm curious if someone knows why this happens
- I'm not aware of a digital camera that can take a 10 minute continuous exposure, but maybe there are special astronomy cameras that can?
- My guess is the camera itself was taking photos of shorter exposure and the final image was composed in post-production, yes.
- Maybe, but also a lot of satellites rotate and so their brightness changes over time.
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- Yeah, I kinda get why astronomers are not particularly happy with satellite constellations.
- And this is just the visible spectrum.
The situation is one order of magnitude worst in radio-astronomy.
It is fair to state that satellite constellations will certainly be the main obstacle to multiple major scientific discoveries in the next decade.
- Opinion: We need to move our astronomical observation equipment off of Earth and onto other bodies, especially radio astronomy, which, unlike telescopes that operate in other wavelengths, is still affected by Earth's emissions in LEO/near-Earth space. We should put a radio telescope on the far side of the moon [0] to benefit from the thousands of kilometers of lunar material separating Earth's emissions from telescopes.
[0] https://doi.org/10.1109/AERO50100.2021.9438165
[1] https://en.wikipedia.org/wiki/Lunar_Crater_Radio_Telescope
- Unfortunately, that seems to be the only solution.
However, it has serious disadvantages. It will exclude the poorer from astronomical research, except within the limits enabled by whatever cooperation the richer will be willing to do with them.
For the richer, that will make astronomical research much more expensive. When even USA, who claims to be the richest country, cuts a lot of the scientific funding, this makes likely a great reduction in the research targets that could be accomplished, even if a Lunar array of telescopes and radiotelescopes and communication relays for them were approved.
While professionals might still be able to do some work, the amateurs will be able less and less to enjoy the sight of the distant Universe.
There are already many years since I have become unable to see the sky that I enjoyed looking at when young, because it cannot be seen from the city where I live, due to light pollution (and high buildings). To see it again, I would have to go somewhere up in the mountains, far from a city or village, but I have not succeeded to do this recently. Even there now you can hardly look at the sky without seeing satellites, and it will only become much worse.
Nowadays there are many children who have never seen even once the sky that our ancestors were seeing every night, so many passages from old texts that mention the sky are unintelligible for them.
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- Our telescopes actually need the (or at least an) atmosphere to function.
There are some classes of observatories, which you cannot build in space but which are still affected by satellites to some degree.
- > Our telescopes actually need the (or at least an) atmosphere to function.
What about Hubble, Chandra, Spitzer, JWST, etc? As of my understanding, the only reason we haven't built radio and and other long-wave telescopes in space is because of their impractical size preventing them from being deployed in orbit.
> There are some classes of observatories, which you cannot build in space but which are still affected by satellites to some degree.
Examples?
- I believe we haven't built radio telescopes in space because we don't need to, and building them in space would be a lot more expensive.
https://commons.wikimedia.org/wiki/File:Atmospheric_electrom...
This shows that wavelengths between ~10cm and ~10m are largely unaffected by the atmosphere, so you wouldn't gain much from putting receivers of those wavelengths in space. Spitzer and JWST (IR), and Chandra (x-ray) operate in bands that are generally blocked by the atmosphere, and Hubble gets better images than a similarly sized earth-based telescope because of the atmospheric distortion (stars don't "twinkle" when you're in space), however there are still earth-based visible light telescopes because you can more easily build a massive one on earth than in space
- What? The atmosphere gets in the way. Ever heard of an (amateur/)astronomer talking about 'good seeing'? That's when the atmosphere is hindering you less than usual.
The limiting factor of passive optical telescopes on earth is the atmosphere.
- They are talking about very high energy gamma-ray telescopes, the Imaging Cherenkov Telescopes.
- Any chance of CubeSat style of telescopes at some point?
- Sure, there have already been some launched and predictably they are only adequate to look at the bright stuff we already knew about from the big telescopes.
A small telescope is just a small telescope even when you put it in space.
- Agreed. It’s the only solution short of a ban on constellations.
- > . We should put a radio telescope on the far side of the moon [0] to benefit from the thousands of kilometers of lunar material separating Earth's emissions from telescopes.
Do you really think a starlink style installation won't be put in orbit of the moon before such a telescope could be funded?
- > Do you really think a starlink style installation won't be put in orbit of the moon before such a telescope could be funded?
There are ITUs rules that forbid that and the far side of the moon is declared as radio quiet.
- Starlinks are already spewing out into supposedly protected radio bands on Earth, good look getting these rules respected on the Moon when they aren't here.
- I'm rebuilding my RSS feed collection, and having pretty astronomy pictures is a fine addition. Thanks!
- So cool! Zoom in to find out: https://zoomhub.net/0w8pN
- Hot take: We're in the first stages of building our own Dyson sphere and therefore comets are only useful in the context of capturing them for that purpose.
;)
- if i could imagine what a Sophon from 3 body problem would look like. this is kind of it.
- That looks so cool, ngl!
