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Isn't the solution more satellites for astronomy? In fact, couldn't the constellation of commercial satellites be used to make a massive distributed hubble tele
by dr_dshiv 6y ago
Isn't the solution more satellites for astronomy? In fact, couldn't the constellation of commercial satellites be used to make a massive distributed hubble telescope?
- simion314 6y agoWill those american billionaires pay say for more European satellites to compensate? What if this were Chinese satellites would you have the same opinion? It would be great if this billionaires would also launch scientific satellites payed from their pocket to compensate, then I would change my mind.
- gambiting 6y agoExactly, if China launched thousands of satellites ruining everyone's astronomy efforts I'm sure there would be an uproar. But US doing it? Fine, business as usual.
- tssva 6y agoThe US isn't doing it. Companies are doing it. As stated in the article the company which is currently planning to place satellites at a height likely to have the greatest impact is OneWeb which is a UK company. It is soon to be controlled by the UK government and an Indian conglomerate. The satellites it launches are built by a joint venture which includes Airbus.
- simion314 6y agoHave you read the paranoia about TikTok? I can see it "Trump: China puts 10000 eyes on the sky, they pretend they want to give Internet to the poor but they have cameras and spy on the traffic, and some reliable sources told me they can release viruses from this satellites in a targets back yard, this needs to stop , I will build a space wall and China will pay for it...
- gambiting 6y ago>>The US isn't doing it. Companies are doing it. Well, that isn't really a useful distinction in any sense of the word. The American companies are doing it, because they are allowed to do so by their country. Most countries which have any kind of space capability have their own space agencies which say what is or isn't ok to launch. If the American space agencies approve things like Starlink, then the pollution of the Earth's view into space isn't purely on Elon Musk.
- ideals 6y agoDue to ITAR regulations SpaceX and Amazon couldn't do it anywhere else either.
- mikro2nd 6y agoThe USA is doing it: The permitting authority is a US government agency taking unilateral decisions that affect the entire globe.
- gorgoiler 6y ago”The US isn’t doing it” Point of order: intercontinental missiles, rockets, and radio telecommunications are highly regulated industries. The US regulators have approved (and not stopped) Starlink on both fronts. I do not know if there’s any international / UN body that performs the same roles?
- dr_dshiv 6y agoI'm sure astronomers would pay for access to a global distributed space-based telescope. So, if there is demand... We are about to have a huge supply.
- gambiting 6y agoI often wonder how come we(as in, humanity) ever only launched a single Hubble telescope. Surely, once you built one, you should be able to build more. Or other countries should be able to take the designs and launch their own versions. Hubble was(and I imagine still is) occupied for weeks at the time taking pictures of certain areas of the sky. Why don't we have 50 Hubbles up in the orbit, doing different things simultaneously? Is it simply because there's no money to do so? I also do remember the story how NASA got a couple decommissioned telescopes from some intelligence agency, which turned out to be an order of magnitude better than Hubble is, and the agency was getting rid of them because they were already outdated. I do remember reading that if those were put into astronomy use they would be a lot better than anything we have currently, but of course those are being used for taking pictures of military sites and tanks, rather than stars.
- welterde 6y agoThe two donated telescopes were the same diameter as the one Hubble had, but were designed to cover a larger field of view (since the small FoV of Hubble wouldn't have been very useful for reconnaissance). But they came without any instruments, so one would have to develop (or adapt the ones from Hubble) to be able to actually use it (and that's were most of the cost is). And the main limitation is quite simply money.. and since a lot of the things that were only possible with HST in the past are possible from the ground now people started focusing on building space observatories for the parts of the optical spectrum that simply cannot be done from the ground (x-ray, far-infrared, gamma-ray).
- samatman 6y agoIf you want an answer to this question, the search string is "James Webb Space Telescope". Be warned: it isn't a pretty picture.
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- BurningFrog 6y agoSpaceX is lowering satellite launch cost by 90% for anyone, Chinese or otherwise. This should start a golden age of space astronomy, even if Elon doesn't give away some telescope launches as PR.
- simion314 6y agoThe launch costs is just a small part of the total costs. You destroy my house and I should be happy you offer me a discount when I buy new blueprints from you.
- iso1210 6y agoMore like "you build something ugly opposite my house"
- simion314 6y agoDisagree, if I make a factory in China that generates some ugly clouds so you can't see your beautiful sky anymore, then if you complain I give you a discount on my airlines so you can fly above the clouds and see the sky for the first time. It could happen if we let companies pollute for free.
- iso1210 6y agoI have a view over the ocean. Along comes Shell and builds an oil rig, thus spoiling my view. I have a view over the ocean, 50 miles up the coast in another country a marina opens, and dozens of sailing ships start arriving over the hour. I have a view, and an airport opens down the road, I'm now under a flight path, not only is my view obscured, I'm getting noise too.
- simion314 6y agoThere is a thing called pollution and light pollution is a thing, So you have a home and someone makes noise so you can't sleep, you have a home and your neighbor has pig shit in his backyard and the smell enters in your yard. Also I amargueing from a public(international) point of view. As an individual with terrible eyes sight I already can't see the stars anymore.
- valuearb 6y agoElon has already cut the cost of putting scientific payloads in space by nearly 80%, what else do you want him to do?
- simion314 6y agoDon't shit on others plate and then offer a discount on cleaning products.
- ColanR 6y ago> It would be great if this billionaires would also launch scientific satellites payed from their pocket to compensate, then I would change my mind. They don't owe you anything.
- simion314 6y agoWe need a sky pollution tax. They owe the public not me personally.
- welterde 6y agoNo. That's not how optics works. The resolution is set by the diffraction limit of the optics, which is mostly limited by the diameter of the aperture. This is not something you can magic away (I am aware that interferometers exist, but those are very limited in their capabilities and don't replace big telescopes). And even with free launches space telescopes are still extremely expensive, since the telescope and all it's instruments has to work in space without any tweaking or possibility for upgrades. Ground based telescopes are used for decades and upgraded with newer instruments over time.
- dr_dshiv 6y agoThis paper suggests otherwise, what are your thoughts? Optical aperture synthesis with electronically connected telescopes https://www.nature.com/articles/ncomms7852 https://www.nature.com/articles/ncomms7852
- welterde 6y agoLike I said interferometers exist but they are very limited in their capabilities. For example the VLT interferometer is limited to observing objects that are brighter than 18th magnitude (and that's using multiple 8m telescopes! Using the auxiliary telescopes which are still 2m you are limited to about 10th magnitude). Something that is easily within the reach of a single telescope less than 50cm in diameter (single 8m telescope can see objects fainter than 25th magnitude - 7 orders of magnitude difference!) - something you can buy for less than 30k$! Interferometry gives you high resolution at the cost of sensitivity. And there way more things that require high sensitivity than high resolution. And I haven't even mentioned spectroscopy, which is hugely important in modern astronomy. And there is no way around having a big light bucket - I wish there was.
- DiogenesKynikos 6y agoFor many reasons, ground-based telescopes will continue to play a major role in astronomy. Space telescopes offer advantages for particular types of observations, but there are many types of observations for which ground-based telescopes are superior. The basic advantages that ground-based telescopes have are: * Larger collecting area, which means more photons collected, which means you can see fainter objects. * With adaptive optics, ground-based telescopes can actually achieve better resolution than space telescopes over small fields of view. * Ground-based telescopes are far easier to maintain and upgrade. * Much looser weight, size, radiation-hardening requirements mean that you can do things on the ground that would just be unthinkable in space. You can attach things like massive spectrometers to ground-based telescopes, without having to worry nearly as much about form factor and weight, or whether radiation will damage your electronics. The advantages that space telescopes have are: * No weather to deal with. * You can observe UV and IR wavelengths which the Earth's atmosphere absorbs or emits in - which is extremely difficult/impossible from the ground. * You can get high resolution over large fields of view. However, you can't reach the same resolution on small fields of view, because ground-based telescopes with a large aperture + adaptive optics will beat you there. Basically, at any fixed budget, you will be able to build a much larger, more complex instrument on the ground. You only go to space when there's a compelling technical reason to do so (e.g., you need to observe UV light).
- dr_dshiv 6y agoGreat run down, thanks for sharing that. I wanted to make sure you saw this article, I wonder how it changes things when we have a "fast, cheap and out of control" approach to science with many cheap satellites. The article is about ground-based telescopes, but seems extendable to space-based telescopes. Optical aperture synthesis with electronically connected telescopes https://www.nature.com/articles/ncomms7852 https://www.nature.com/articles/ncomms7852