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On the one hand the constellations are doing considerable damage to surface based astronomy. On the other hand they are funding an enormously lower cost of acce
by delichon 3y ago
On the one hand the constellations are doing considerable damage to surface based astronomy. On the other hand they are funding an enormously lower cost of access to orbit and beyond for astronomy up in the sky.
- marcosdumay 3y agoYes, the future of astronomy is in space. If the satellites don't disrupt it, light pollution will anyway, or best case, it will be disrupted by atmospheric pollution. There's no lack of clear skies in space.
- DiogenesKynikos 3y agoThe future of astronomy is both on the ground and in space. There are so many things that you can only conceivably do from the ground. You can build vastly larger telescopes on the ground, you can install far heavier instruments (like cameras and spectrographs) on them, you can upgrade and repair components much more easily. You can build massive arrays of radio telescopes. You get the point. There are some things you can only do from space, or that are better in space, but saying that everything will be done in space is like saying we only need laptops and don't need datacenters. You need both.
- mercutio2 3y agoAre there really a lot of ground based telescope components larger than Starship's fairing? I'm just not seeing the argument for there being any telescope function that wouldn't be better done in orbit, at Starship payload prices.
- Retric 3y agoYes, though I guess it depends on what you mean by lots: https://en.wikipedia.org/wiki/List_of_largest_optical_reflecting_telescopes https://en.wikipedia.org/wiki/List_of_largest_optical_reflec.... Critically the 30+m monsters under construction have only recently become feasible on the Earh let alone in space, and much smaller instruments still provide significant value today. There’s a much longer list of large radio based telescopes which have minimal advantages in space to the point where we haven’t launched any, and they are also negatively impacted by constellations. Also, several types of observations don’t really benefit from being in space. If you want to track killer asteroids space doesn’t provide much advantage even if you could get there for 100$/kg. IMO the issue here isn’t satellites, it’s that they can harm multi billion dollar investments at zero cost to themselves. If you’re very clearly causing 10’s of millions in damages you really should be compensating the people affected.
- TeMPOraL 2y ago> There’s a much longer list of large radio based telescopes which have minimal advantages in space to the point where we haven’t launched any What if they could be put behind the Moon, completely shielding them from Earth RF emissions? It's been a cost-prohibitive idea now, but might not be for much longer.
- sapiogram 2y agoThe largest filled-aperture radio telescope in the world has a 500-meter diameter, and reportedly only cost $180 million. For comparison, the International Space Station costs $3 billion per year just to operate. Doing stuff in space is expensive.
- TeMPOraL 2y agoRight, but the whole reason people are so excited about SpaceX is because they're making the costs of doing stuff in space drop like a stone.
- sapiogram 2y agoFor large (>10m) telescopes, it doesn't matter much, because no one is building rockets with big enough fairings. Even if the cost of launching to LEO was $0, in-orbit unfolding/assembly is a bottomless hole of engineering complexity that you cannot avoid. Again, see JWST/ISS.
- petsfed 2y agoI count 13 on wikipedia's list of the largest telescopes. There are 3 more currently under construction. The evocatively named "Extremely Large Telescope" is estimated to cost about $1 billion USD. Who knows how much it will actually cost, but for comparison, that's about $400 million less (adjusted for inflation) than the budgeted cost of the Webb telescope, which is about 1/6 the planned size (and therefore 1/36 the light collecting capability). edit: italicized above. The Webb ended up costing $10 billion, so the savings could be even larger
- mercutio2 2y agoBut the point is that Webb was vastly over-engineered because we needed to get value out of every ounce of mass at the very high costs of legacy launch providers, and even more compromised because of Ariane 5’s tiny fairing. You could build Webb for vastly, vastly less money if it launched on Starship, not just per unit of mass; volume is at much less of a premium in the new regime. You can’t quite fit ELT pre-constructed into a single Starship, it’s true. But it’s built out of segmented mirrors. It doesn’t have to arrive on station in one piece.
- ketralnis 3y agoA: yeah we're hurting you but if we didn't, B & C would B: yeah we're hurting you but if we didn't, A & C would C: yeah we're hurting you but if we didn't, A & B would I guess it’s nobody’s fault then
- marcosdumay 3y agoA lot of people really want A & B. Way more than how many want your work. But well, any one is free to go fight the tide.
- bmitc 3y agoThat needs some citations. The James Webb Telescope's mirror is 6.5m in diameter. It took decades and billions of dollars of overruns and a prayer to launch and work correctly. There is no hope of most hardware repairs. That mirror size pails in comparison to what can be accomplished via ground based observatories for much, much cheaper. And the available modes of operation are completely different between space and ground. For example, space observatories are using decades old instrumentation techniques, hardware, and software. And that's just for starters. We cannot do astronomy via space exclusively. For me personally, I never wanted to see something like Starlink with my bare eyes, and I have several times. It's beyond annoying to me that a company has been able to unilaterally pollute the Earth's sky.
- _dain_ 3y ago> That needs some citations. The James Webb Telescope's mirror is 6.5m in diameter. It took decades and billions of dollars of overruns and a prayer to launch and work correctly. There is no hope of most hardware repairs. Because it had to get launched folded up, because the launch vehicles were so space- and mass-constrained. The unfolding mechanism was enormously complicated and added to much of the cost. Now we can send up bigger, heavier objects for much less money. The 6.5m mirror fits comfortably inside Starship's cargo bay, unfolded. JWST is a one-off clockwork masterpiece; future space telescopes will come off an assembly line. There will be thousands in orbit, pointed at every part of the heavens simultaneously.
- Cacti 3y agoIs this something we have evidence for, or is this just in theory?
- delichon 3y agoSpaceX built the biggest constellation to date, and is using the profits to build Falcons while designing Starships. Check out the resulting cost per kilo to orbit: https://ourworldindata.org/grapher/cost-space-launches-low-earth-orbit https://ourworldindata.org/grapher/cost-space-launches-low-e... That's pretty good for theory.
- bmitc 3y agoThe theoretical part is whether that's actually useful for not. Cost per kilo to orbit doesn't magically solve astronomical observation problems.
- delichon 3y agoDon't Chandra, Webb and Hubble, et. al. sufficiently prove the usefulness?
- p_j_w 2y agoThe cost of getting those into space is a relatively small part of the overall cost. The amount of cost benefit one of these telescopes would see just to the cost reductions gained specifically because of Starlink are insignificant.
- ThrowawayTestr 2y ago> The cost of getting those into space is a relatively small part of the overall cost. Are you sure about that?
- alethiophile 2y agoThe cost of launch is small-ish compared to the total program cost, but the limitations on launch condition the engineering requirements in ways that inflate the engineering costs. JWST had to be built as an insane on-orbit autonomous origami project because its mirror couldn't fit in a fairing unfolded. Repeat for ten thousand other decisions that are made in order to optimize weight or volume. If you can launch a hundred tons to orbit for $5M, you can just make a huge dumb cheap telescope and throw a dozen of them up there. Quantity covers a multitude of sins.
- Almondsetat 3y agoExactly my thoughts. Scientists drool at the few telescopes we have in orbit. If we could launch more of them for less money at the expense of a busier night sky I don't think they would want to miss on that
- hehdhdjehehegwv 3y ago[flagged]
- stouset 3y agoMegaconstellations are not a problem for kids looking through telescopes. If anything it’s additional things to wonder at in amazement.
- pfdietz 2y agoIndeed. The big obstacle for kids is when the entire sky is washed out with sodium vapor light and maybe you can see Vega.
- rgmerk 2y agoGrowing up in a small town, I could see thousands of stars on a clear night. In a major metropolitan area where I live now, it’s hundreds. When I visited Beijing for three weeks, I think there was one night where the pollution cleared sufficiently to see any stars at all; I think I saw three or four.
- harimau777 2y agoIt seems to me that one problem is that regular people who are interested in astronomy don't have access to space based telescopes. I'm not sure I'd want to live in a world where there's that degree of class divide between astronomers who do and do not have access to that kind of funding.