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I'm reluctant to criticise Destin as he is infinitely more knowledgeable about this than I am BUT that video did not convince me. I see Artemis as an attempt t

I'm reluctant to criticise Destin as he is infinitely more knowledgeable about this than I am BUT that video did not convince me. I see Artemis as an attempt to industrialise the process of getting humans and large volumes of materials to the Moon, ultimately as a stepping stone to Mars. This isn't a proof of concept self-contained "mission" like Apollo was. It felt a bit like saying the global aviation system is overengineered compared to the Wright Flyer. I don't see why it really matters if it needs 15, 20 or even 50 reusable vessels for orbital refuelling as long as that process is repeatable and safe. That said, it's been a few months since I watched that video so I may not have done a good job here of remembering what my criticisms even were.

consumer451 2y ago
The 15 launches is a big deal, because it requires either a dozen or so Starship Tanker full stacks, or very-rapid reuse to be fully solved. But it's probably solvable, and otherwise SpaceX can "just" build a dozen Tankers, and reuse them slowly. It's solvable, but personally, I'm not all that optimistic on the timeline though. The shocking thing for me from that video was learning how useless the Lunar Gateway is most of the time due to its near-rectilinear halo orbit. This leads it to be only within range for rescuing those on the moon, for a couple days a week. Why does Gateway have this type of orbit? Because the Senate Launch System doesn't have the delta-v to get the capsule to circularized low-lunar orbit. We designed a moon rocket, which can't get to the moon.
- JumpCrisscross 2y ago
  > leads it to be only within range for rescuing those on the moon, for a couple days a week I genuinely never heard about the Gateway being there for rescue until Destin's talk. (Not saying he invented it. Just that it wasn't what it was advertised for.) Compared to just landing a spare Earth ascent vehicle, it seems like a stupid way to solve for our lack of low-gravity trauma medicine experience. > Why does Gateway have this type of orbit? Because the Senate Launch System doesn't have the delta-v to get the capsule to circularized low-lunar orbit NRHO also minimises communication black-outs with Earth. With the Gateway in orbit, other craft in circular orbit can maintain continuous contact with the Earth.
  - consumer451 2y ago
    He mentions the blackout problem, but having a constellation of a couple relay sats is likely going to happen anyway if IIRC.
    - JumpCrisscross 2y ago
      > having a constellation of a couple relay sats is likely going to happen anyway if IIRC But why would you set that as a pre-requisite? The Gateway is also, as I understand it, a staging ground for testing habitation for a vehicle to Mars.
      - consumer451 2y ago
        > But why would you set that as a pre-requisite? Well, the argument in his video is that there are multi-day gaps in the ability to rescue astronauts off the moon. Balancing that out with a few very small relay satellites, I would pay for a couple Electron launches for the relay, and have a lifeboat capability 24/7. > The Gateway is also, as I understand it, a staging ground for testing habitation for a vehicle to Mars. I have heard that as well, but what I don't understand is how a higher orbit simulates a Mars trip much better. I mean, either way you are not inside a magnetosphere, right? I guess in low-lunar orbit you are more shaded from solar wind by the moon half the time?
        JumpCrisscross 2y ago
        > the argument in his video is that there are multi-day gaps in the ability to rescue astronauts off the moon Right, which is where he loses me--this is not why we have a Gateway. > Balancing that out with a few very small relay satellites, I would pay for a couple Electron launches for the relay, and have a lifeboat capability 24/7 Building a communications relay constellation isn't a simple task. It's on the roadmap for Artemis. > what I don't understand is how a higher orbit simulates a Mars trip much better The high orbit is irrelevant to this aim. You'd get the same deep-space habitation science from a low, circularised orbit. The high orbit is for creating a one-and-done communication relay.
- rbanffy 2y ago
  > The 15 launches is a big deal, because it requires either a dozen or so Starship Tanker full stacks, It's more a logistics problem than anything else. If a Superheavy and Tanker takes 3 weeks to relaunch, you build 3 to launch weekly and 21 to launch daily. Now you need to have 21 processing facilities and 21 times more people to do that. Launch pads, landing pads, and Mechazillas don't need that long to recover, so you can build just a couple extra ones with each one serving a group of processing facilities.

consumer451 2y ago

The 15 launches is a big deal, because it requires either a dozen or so Starship Tanker full stacks, or very-rapid reuse to be fully solved. But it's probably solvable, and otherwise SpaceX can "just" build a dozen Tankers, and reuse them slowly. It's solvable, but personally, I'm not all that optimistic on the timeline though. The shocking thing for me from that video was learning how useless the Lunar Gateway is most of the time due to its near-rectilinear halo orbit. This leads it to be only within range for rescuing those on the moon, for a couple days a week. Why does Gateway have this type of orbit? Because the Senate Launch System doesn't have the delta-v to get the capsule to circularized low-lunar orbit. We designed a moon rocket, which can't get to the moon.

JumpCrisscross 2y ago
> leads it to be only within range for rescuing those on the moon, for a couple days a week I genuinely never heard about the Gateway being there for rescue until Destin's talk. (Not saying he invented it. Just that it wasn't what it was advertised for.) Compared to just landing a spare Earth ascent vehicle, it seems like a stupid way to solve for our lack of low-gravity trauma medicine experience. > Why does Gateway have this type of orbit? Because the Senate Launch System doesn't have the delta-v to get the capsule to circularized low-lunar orbit NRHO also minimises communication black-outs with Earth. With the Gateway in orbit, other craft in circular orbit can maintain continuous contact with the Earth.
- consumer451 2y ago
  He mentions the blackout problem, but having a constellation of a couple relay sats is likely going to happen anyway if IIRC.
  - JumpCrisscross 2y ago
    > having a constellation of a couple relay sats is likely going to happen anyway if IIRC But why would you set that as a pre-requisite? The Gateway is also, as I understand it, a staging ground for testing habitation for a vehicle to Mars.
    - consumer451 2y ago
      > But why would you set that as a pre-requisite? Well, the argument in his video is that there are multi-day gaps in the ability to rescue astronauts off the moon. Balancing that out with a few very small relay satellites, I would pay for a couple Electron launches for the relay, and have a lifeboat capability 24/7. > The Gateway is also, as I understand it, a staging ground for testing habitation for a vehicle to Mars. I have heard that as well, but what I don't understand is how a higher orbit simulates a Mars trip much better. I mean, either way you are not inside a magnetosphere, right? I guess in low-lunar orbit you are more shaded from solar wind by the moon half the time?
      - JumpCrisscross 2y ago
        > the argument in his video is that there are multi-day gaps in the ability to rescue astronauts off the moon Right, which is where he loses me--this is not why we have a Gateway. > Balancing that out with a few very small relay satellites, I would pay for a couple Electron launches for the relay, and have a lifeboat capability 24/7 Building a communications relay constellation isn't a simple task. It's on the roadmap for Artemis. > what I don't understand is how a higher orbit simulates a Mars trip much better The high orbit is irrelevant to this aim. You'd get the same deep-space habitation science from a low, circularised orbit. The high orbit is for creating a one-and-done communication relay.
rbanffy 2y ago
> The 15 launches is a big deal, because it requires either a dozen or so Starship Tanker full stacks, It's more a logistics problem than anything else. If a Superheavy and Tanker takes 3 weeks to relaunch, you build 3 to launch weekly and 21 to launch daily. Now you need to have 21 processing facilities and 21 times more people to do that. Launch pads, landing pads, and Mechazillas don't need that long to recover, so you can build just a couple extra ones with each one serving a group of processing facilities.