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Perhaps a deal could be worked out where the satellite companies also have to launch Atacama-scale telescopes, where Musk et al have to pay for the difference i

Perhaps a deal could be worked out where the satellite companies also have to launch Atacama-scale telescopes, where Musk et al have to pay for the difference in cost between Atacama and orbit.

Rebelgecko 7y ago
Telescopes are pretty big. It would take 5-10 Falcon 9 launches to put something with that mass into orbit (although in space you could probably have a lighter mechanism for orienting el/az). The telescope's mirror is also too big to physically fit into the F9's fairing. Once you get it there, you need to assemble it and keep it running. Maintenance is a real doozy— building a telescope on Earth is expensive. Building a telescope in space is even harder, since it won't be regularly serviced and you have to overengineer it. A typical space telescope still costs an order of magnitude more than a recordbreakingly expensive earth-based one.
- DennisP 7y ago
  Yes but the point of Starlink is to fund Starship, which is a lot bigger than Falcon 9. Its fairing is 9 meters in diameter[0], large enough for all but the top six land-based telescopes.[1] Its payload is 100+ tonnes, five times larger than Falcon 9's. Starship is also a lot cheaper per kilogram of payload; at scale, as low as $20/kg. Cheap launch also makes your satellites cheaper to build, since it's less of a disaster if you have to replace them. Musk has already floated the idea of building a second-generation Starship with an 18-meter fairing.[2] [0] https://www.spacex.com/starship https://www.spacex.com/starship [1] https://en.wikipedia.org/wiki/List_of_largest_optical_reflecting_telescopes https://en.wikipedia.org/wiki/List_of_largest_optical_reflec... [2] https://www.teslarati.com/spacex-elon-musk-starship-the-next-generation/ https://www.teslarati.com/spacex-elon-musk-starship-the-next...
  - Rebelgecko 7y ago
    Even if it becomes physically possible to launch them at some point in the future, I should have mentioned that launch costs are only a relatively small part of the cost of space based telescopes. As launch prices continue to go down, this will be more and more true in the future. For the upcoming JWST, the launch is only costing around 1-2% of the overall price. It will be a similar number for WFIRST if that gets built on budget. The expensive part is engineering a device that can assemble itself in outer space, and continue to run 24/7 for decades without regular maintainence.
    - DennisP 7y ago
      You don't need much orbital assembly if you can launch something with a 9-meter or 18-meter diameter. And again, cheaper launch cost also makes space hardware cheaper; you can afford to make it heavier, and you can afford to replace it if necessary.
    - avmich 7y ago
      This is outdated model regarding space telescopes. With radically cheaper launches, it's becoming quite possible - not now, but somewhat soon - to actually service telescopes, with conditions superior to those under which the Hubble was serviced by Shuttle teams. With radically cheaper launches, it's not necessary to ensure the 'scope runs 24/7 for decades without regular maintenance. It can even be replaced regularly; including by bringing it to Earth, servicing it and sending back. Launch prices are going to drop, but so is the necessity to be extremely reliable for the space equipment, for the same two reasons: 1) it's comparatively easy to get to it for a service and 2) it's comparatively easy to just send a replacement if needed. With space manufacturing advancements still ahead of us - we didn't really experimented with making telescopes in orbit - it's not clear if space telescopes won't outperform terran ones. Space telescopes are going to have advantages like "atmosphere doesn't block part of the spectrum" and "there is no need to make a big structure capable withstanding 1g gravity". It's still crucially important to be able to do terran-based astronomy, and that's a problem, but there is no doubt that the astronomy revolution which started with Hubble still has major advancements to have in the near future.
      - nickik 7y ago
        Also we are gone move into types of systems where its not one thing anymore. We increasingly telescopes that are consistent of multiple parts sometimes including things like a sun shade that operates far away from the rest of the parts. All of these things are only gone be possible once launch prices are cheaper and Starlink (or something like it) is a major part of how that can happen.
      - Rebelgecko 7y ago
        Radically cheaper launches will still be significantly more expensive than current maintenance contracts. Even if we have infinitely reusable rockets in the future, you're still looking at millions of $ in fuel costs for a servicing trip. I am personally not as optimistic about "soon". If you send a technician out to the Earth-Sun L2 point (where JWST will be) so that she can throw some grease on a gear or spray WD-40 on a reaction wheel, she'll be 4 times further from Earth than any human has ever gone. Although there may be some synergy with future Lunar/Martian missions, there's a lot of work that needs to be done to figure out how to do that safely. I think L2 is the safest Lagrange point w.r.t radiation, but it's still potentially deadly. >"there is no need to make a big structure capable withstanding 1g gravity". While the overall structure may not need to withstand 1g continuously, you still need to design it to as much as 6 Gs of acceleration during launch (as well as significant lateral acceleration, and occasional shocks in the dozens or hundreds of gs).

Perhaps a deal could be worked out where the satellite companies also have to launch Atacama-scale telescopes, where Musk et al have to pay for the difference in cost between Atacama and orbit.

Rebelgecko 7y ago

Telescopes are pretty big. It would take 5-10 Falcon 9 launches to put something with that mass into orbit (although in space you could probably have a lighter mechanism for orienting el/az). The telescope's mirror is also too big to physically fit into the F9's fairing. Once you get it there, you need to assemble it and keep it running. Maintenance is a real doozy— building a telescope on Earth is expensive. Building a telescope in space is even harder, since it won't be regularly serviced and you have to overengineer it. A typical space telescope still costs an order of magnitude more than a recordbreakingly expensive earth-based one.

DennisP 7y ago
Yes but the point of Starlink is to fund Starship, which is a lot bigger than Falcon 9. Its fairing is 9 meters in diameter[0], large enough for all but the top six land-based telescopes.[1] Its payload is 100+ tonnes, five times larger than Falcon 9's. Starship is also a lot cheaper per kilogram of payload; at scale, as low as $20/kg. Cheap launch also makes your satellites cheaper to build, since it's less of a disaster if you have to replace them. Musk has already floated the idea of building a second-generation Starship with an 18-meter fairing.[2] [0] https://www.spacex.com/starship https://www.spacex.com/starship [1] https://en.wikipedia.org/wiki/List_of_largest_optical_reflecting_telescopes https://en.wikipedia.org/wiki/List_of_largest_optical_reflec... [2] https://www.teslarati.com/spacex-elon-musk-starship-the-next-generation/ https://www.teslarati.com/spacex-elon-musk-starship-the-next...
- Rebelgecko 7y ago
  Even if it becomes physically possible to launch them at some point in the future, I should have mentioned that launch costs are only a relatively small part of the cost of space based telescopes. As launch prices continue to go down, this will be more and more true in the future. For the upcoming JWST, the launch is only costing around 1-2% of the overall price. It will be a similar number for WFIRST if that gets built on budget. The expensive part is engineering a device that can assemble itself in outer space, and continue to run 24/7 for decades without regular maintainence.
  - DennisP 7y ago
    You don't need much orbital assembly if you can launch something with a 9-meter or 18-meter diameter. And again, cheaper launch cost also makes space hardware cheaper; you can afford to make it heavier, and you can afford to replace it if necessary.
  - avmich 7y ago
    This is outdated model regarding space telescopes. With radically cheaper launches, it's becoming quite possible - not now, but somewhat soon - to actually service telescopes, with conditions superior to those under which the Hubble was serviced by Shuttle teams. With radically cheaper launches, it's not necessary to ensure the 'scope runs 24/7 for decades without regular maintenance. It can even be replaced regularly; including by bringing it to Earth, servicing it and sending back. Launch prices are going to drop, but so is the necessity to be extremely reliable for the space equipment, for the same two reasons: 1) it's comparatively easy to get to it for a service and 2) it's comparatively easy to just send a replacement if needed. With space manufacturing advancements still ahead of us - we didn't really experimented with making telescopes in orbit - it's not clear if space telescopes won't outperform terran ones. Space telescopes are going to have advantages like "atmosphere doesn't block part of the spectrum" and "there is no need to make a big structure capable withstanding 1g gravity". It's still crucially important to be able to do terran-based astronomy, and that's a problem, but there is no doubt that the astronomy revolution which started with Hubble still has major advancements to have in the near future.
    - nickik 7y ago
      Also we are gone move into types of systems where its not one thing anymore. We increasingly telescopes that are consistent of multiple parts sometimes including things like a sun shade that operates far away from the rest of the parts. All of these things are only gone be possible once launch prices are cheaper and Starlink (or something like it) is a major part of how that can happen.
    - Rebelgecko 7y ago
      Radically cheaper launches will still be significantly more expensive than current maintenance contracts. Even if we have infinitely reusable rockets in the future, you're still looking at millions of $ in fuel costs for a servicing trip. I am personally not as optimistic about "soon". If you send a technician out to the Earth-Sun L2 point (where JWST will be) so that she can throw some grease on a gear or spray WD-40 on a reaction wheel, she'll be 4 times further from Earth than any human has ever gone. Although there may be some synergy with future Lunar/Martian missions, there's a lot of work that needs to be done to figure out how to do that safely. I think L2 is the safest Lagrange point w.r.t radiation, but it's still potentially deadly. >"there is no need to make a big structure capable withstanding 1g gravity". While the overall structure may not need to withstand 1g continuously, you still need to design it to as much as 6 Gs of acceleration during launch (as well as significant lateral acceleration, and occasional shocks in the dozens or hundreds of gs).