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Note that if you send a human crew you don’t really want to go slow because of cosmic rays (not to mention being locked in a can). Autonomous robotics have come

Note that if you send a human crew you don’t really want to go slow because of cosmic rays (not to mention being locked in a can). Autonomous robotics have come a long way but I don’t think they’re ready for state of the art telescope repair.

avmich 5y ago
Soviet spaceship TKS ( https://en.wikipedia.org/wiki/TKS_spacecraft https://en.wikipedia.org/wiki/TKS_spacecraft ) was a whole orbital station module together with return capsule, developed up to mid-1980-s. It was supposed to be launched manned, and crew members - up to 3 - would have a lot of space available to them right after getting to orbit. So it could be considered as a long-range mission spacecraft; it would need to have a booster module, but that's solvable (i.e. Agena for Gemini-10 flight https://en.wikipedia.org/wiki/Agena_target_vehicle https://en.wikipedia.org/wiki/Agena_target_vehicle ).
- hguant 5y ago
  Right, but the timeline of getting a human certified flight vehicle for a mission of that duration, carrying the amount of fuel needed for the "back again" portion of the trip is probably equivalent to the (delayed and prolonged) development time of the JWT. We're on track for a manned moon mission in approximately 10 years, and the 'best minds' view building a robotic refueling station in cis-lunar space as the ideal means of making the launch realistically happen, owing to the issues of fuel weights. The rocket to do this mission doesn't exist, the space craft to go there doesn't exist, and the designs we do have (crew dragon, soyuz) aren't easily retrofitted to the mission requirements of going out to L2. Theoretically solvable, yes. Practically impossible, especially when building another JWT would cost less, take less time (just do it again, but better!), and most importantly, risk fewer lives (0, by my count).
  - avmich 5y ago
    > Practically impossible, Yes, most likely it won't be done, but that doesn't mean impossible. Just four times farther than the Moon. Flight to the Moon - 4 days, so maybe a couple of weeks here - at most. Getting to Moon orbit from translunar - about 1 km/s, getting back - about the same, here it won't be more. > especially when building another JWT would cost less, I highly doubt. JWT is a unique device - telescope at the bleeding edge of capabilities of humanity. And in comparison we had close to 300 manned flights, about 10 of which - above LEO, and more than half a dozen of space tourists - no offense intended, just in case. So, no, I don't believe a manned spacecraft for a longer-duration mission can't be created in a few years. And the space tech capabilities are actually higher than in 1960-s - look at the SpaceX progress. > take less time (just do it again, but better!), Less maybe than those 2,5 decades it took first. But less than 5 years? Unlikely. And in 5 years you may have Starship flying, Starliner flying, Dream Chaser flying, SLS/Orion in a better shape, Falcon-9 Heavy with more flights, possibly Vulcan getting ready - Vulcan has some advanced booster stage, by the way, suitable for more complex missions. > and most importantly, risk fewer lives (0, by my count). Possibly - again, in L2 we don't need to land or lift off, while we're still going to to that with the Moon, so I'm not sure if L2 mission would be riskier than a Moon landing flight. But in exchange we'll have those two benefits: 1) service a unique device 2) gain important experience in human spaceflight Those aren't small benefits.
    - hguant 5y ago
      I was typing up a response, but "space enthusiast" on your profile sums it up - you're statements show your enthusiasm, but not any real understanding of the problem space. The statements above are wildly optimistic, and don't actually take into account the actual capabilities and capacities of the launch vehicles in question. Furthermore, you're showing an extreme disregard for the actual engineering problems at hand here. It's a multi-decade process to design, build, and certify a launch vehicle _for LEO_. Handwaving "we can do it in 5 years" because the sales teams at SpaceX said so is, frankly, not a real answer. Talking about the "good state" the SLS/Orion are going to be in is, frankly, optimistic to the point of being naive. Spewing factoids about spacecraft that don't actually exist beyond a "we blew it up on a launch pad" isn't an answer - it's a pipe dream. Furthermore, you've deftly evaded even acknowledging the core problem - we don't have a space craft with an engine that can do the "back again" part of an L2 mission. That capacity literally doesn't exist right now. You can't just whistle up a rocket that works a few million miles from home.
      - avmich 5y ago
        It reminds me a lot some conversations with Energomash back in the days of particularly young SpaceX. Since then most players in world space market acknowledged that progress is possible. Some, unfortunately, didn't.
  - ufmace 5y ago
    I'd say the real issue isn't even getting people there, but being properly prepared for the repair. Would we be able to know 100% everything that went wrong? Would we be sure that the right tools and parts for repair were aboard the repair craft? Maybe to be sure of a successful repair, we'd have to bring most of a whole new satellite anyways. Maybe it's easier to just send an actual whole new satellite up instead.

avmich 5y ago

Soviet spaceship TKS ( https://en.wikipedia.org/wiki/TKS_spacecraft https://en.wikipedia.org/wiki/TKS_spacecraft ) was a whole orbital station module together with return capsule, developed up to mid-1980-s. It was supposed to be launched manned, and crew members - up to 3 - would have a lot of space available to them right after getting to orbit. So it could be considered as a long-range mission spacecraft; it would need to have a booster module, but that's solvable (i.e. Agena for Gemini-10 flight https://en.wikipedia.org/wiki/Agena_target_vehicle https://en.wikipedia.org/wiki/Agena_target_vehicle ).

hguant 5y ago
Right, but the timeline of getting a human certified flight vehicle for a mission of that duration, carrying the amount of fuel needed for the "back again" portion of the trip is probably equivalent to the (delayed and prolonged) development time of the JWT. We're on track for a manned moon mission in approximately 10 years, and the 'best minds' view building a robotic refueling station in cis-lunar space as the ideal means of making the launch realistically happen, owing to the issues of fuel weights. The rocket to do this mission doesn't exist, the space craft to go there doesn't exist, and the designs we do have (crew dragon, soyuz) aren't easily retrofitted to the mission requirements of going out to L2. Theoretically solvable, yes. Practically impossible, especially when building another JWT would cost less, take less time (just do it again, but better!), and most importantly, risk fewer lives (0, by my count).
- avmich 5y ago
  > Practically impossible, Yes, most likely it won't be done, but that doesn't mean impossible. Just four times farther than the Moon. Flight to the Moon - 4 days, so maybe a couple of weeks here - at most. Getting to Moon orbit from translunar - about 1 km/s, getting back - about the same, here it won't be more. > especially when building another JWT would cost less, I highly doubt. JWT is a unique device - telescope at the bleeding edge of capabilities of humanity. And in comparison we had close to 300 manned flights, about 10 of which - above LEO, and more than half a dozen of space tourists - no offense intended, just in case. So, no, I don't believe a manned spacecraft for a longer-duration mission can't be created in a few years. And the space tech capabilities are actually higher than in 1960-s - look at the SpaceX progress. > take less time (just do it again, but better!), Less maybe than those 2,5 decades it took first. But less than 5 years? Unlikely. And in 5 years you may have Starship flying, Starliner flying, Dream Chaser flying, SLS/Orion in a better shape, Falcon-9 Heavy with more flights, possibly Vulcan getting ready - Vulcan has some advanced booster stage, by the way, suitable for more complex missions. > and most importantly, risk fewer lives (0, by my count). Possibly - again, in L2 we don't need to land or lift off, while we're still going to to that with the Moon, so I'm not sure if L2 mission would be riskier than a Moon landing flight. But in exchange we'll have those two benefits: 1) service a unique device 2) gain important experience in human spaceflight Those aren't small benefits.
  - hguant 5y ago
    I was typing up a response, but "space enthusiast" on your profile sums it up - you're statements show your enthusiasm, but not any real understanding of the problem space. The statements above are wildly optimistic, and don't actually take into account the actual capabilities and capacities of the launch vehicles in question. Furthermore, you're showing an extreme disregard for the actual engineering problems at hand here. It's a multi-decade process to design, build, and certify a launch vehicle _for LEO_. Handwaving "we can do it in 5 years" because the sales teams at SpaceX said so is, frankly, not a real answer. Talking about the "good state" the SLS/Orion are going to be in is, frankly, optimistic to the point of being naive. Spewing factoids about spacecraft that don't actually exist beyond a "we blew it up on a launch pad" isn't an answer - it's a pipe dream. Furthermore, you've deftly evaded even acknowledging the core problem - we don't have a space craft with an engine that can do the "back again" part of an L2 mission. That capacity literally doesn't exist right now. You can't just whistle up a rocket that works a few million miles from home.
    - avmich 5y ago
      It reminds me a lot some conversations with Energomash back in the days of particularly young SpaceX. Since then most players in world space market acknowledged that progress is possible. Some, unfortunately, didn't.
- ufmace 5y ago
  I'd say the real issue isn't even getting people there, but being properly prepared for the repair. Would we be able to know 100% everything that went wrong? Would we be sure that the right tools and parts for repair were aboard the repair craft? Maybe to be sure of a successful repair, we'd have to bring most of a whole new satellite anyways. Maybe it's easier to just send an actual whole new satellite up instead.