5 ms·

> Putting 1000 people on a ship seems like a pipe-dream adjacent to full-self driving at this point. we have centuries of experience with doing the exact same

> Putting 1000 people on a ship seems like a pipe-dream adjacent to full-self driving at this point. we have centuries of experience with doing the exact same thing to people at sea. > for the cost of a manned program we could be sending out dozens of probes and rovers Why not both? I see the value in each.

micromacrofoot 3y ago
Eventually yes, but it seems we're putting the cart before the horse. I really hope it goes well and we end up accelerating things with another space race, this is the best outcome and maybe this is why we're shooting for manned Mars missions... but it's risky. A crew of dead astronauts on Mars could have the opposite effect. Imagine if Nixon really had to deliver that failure message about the moon landing, space exploration could be even worse off than it is now.
kjs3 3y ago
I think sending a person across the ocean, under an atmosphere, protected from radiation, with gravity isn't "the exact same" thing as through space. Much less 1000. Pretending that it is...charitably...is silly.
- PaulDavisThe1st 3y ago
  True, but this works in reverse too. Much harder to get the initial, small scale version of a cycler-based transit system established. But then, because you don't have an atmosphere or ocean or particularly noticeable gravity, scaling it up it probably much, much easier than doing so for ocean-going vessels and the like.
  - kjs3 3y ago
    Maybe? My point is if you are going to do it, start with a mental model that fits the task, not one that both isn't remotely the same engineering challenge and ignores the actual hard problems.
    - PaulDavisThe1st 3y ago
      Well, we're a good part of the way towards being able to move people from the earth's surface into orbit. Somewhere between, say, 20% and 80%. If that claim is true, then it seems reasonable to be thinking about what comes next, and building a small cycler seems like a potentially reasonable choice. If we can indeed build a small cycler, then getting to a big one may be much easier than going from a small yacht to a transoceanic liner.
      - accrual 3y ago
        > If we can indeed build a small cycler, then getting to a big one may be much easier than going from a small yacht to a transoceanic liner. It still falls apart a bit due to the rocket equation. [0] When you're in a safe harbor on earth, it's somewhat simple to increase the size of your boat, most of the rules stay the same. But as you build bigger cyclers, one will either need bigger rockets or more rockets and then possibly assembly/docking in space, so it's definitely more complicated than making a larger displacement in the water. [0] https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation
        PaulDavisThe1st 3y ago
        I thought that the whole point of a cycler was to reduce the need for rocket propulsion to a vanishingly small part of the system.
        accrual 3y ago
        That is true. My comment was more about the initial setup of a larger cycler. Larger cyclers will cost exponentially more rocket mass/fuel/complexity than a smaller cycler. But once in orbit, yes, the design reduces overall fuel costs.
        ben_w 3y ago
        Rocket equation makes faster exponentially difficult; merely heavier scales linearly.

micromacrofoot 3y ago

Eventually yes, but it seems we're putting the cart before the horse. I really hope it goes well and we end up accelerating things with another space race, this is the best outcome and maybe this is why we're shooting for manned Mars missions... but it's risky. A crew of dead astronauts on Mars could have the opposite effect. Imagine if Nixon really had to deliver that failure message about the moon landing, space exploration could be even worse off than it is now.

kjs3 3y ago

I think sending a person across the ocean, under an atmosphere, protected from radiation, with gravity isn't "the exact same" thing as through space. Much less 1000. Pretending that it is...charitably...is silly.

PaulDavisThe1st 3y ago
True, but this works in reverse too. Much harder to get the initial, small scale version of a cycler-based transit system established. But then, because you don't have an atmosphere or ocean or particularly noticeable gravity, scaling it up it probably much, much easier than doing so for ocean-going vessels and the like.
- kjs3 3y ago
  Maybe? My point is if you are going to do it, start with a mental model that fits the task, not one that both isn't remotely the same engineering challenge and ignores the actual hard problems.
  - PaulDavisThe1st 3y ago
    Well, we're a good part of the way towards being able to move people from the earth's surface into orbit. Somewhere between, say, 20% and 80%. If that claim is true, then it seems reasonable to be thinking about what comes next, and building a small cycler seems like a potentially reasonable choice. If we can indeed build a small cycler, then getting to a big one may be much easier than going from a small yacht to a transoceanic liner.
    - accrual 3y ago
      > If we can indeed build a small cycler, then getting to a big one may be much easier than going from a small yacht to a transoceanic liner. It still falls apart a bit due to the rocket equation. [0] When you're in a safe harbor on earth, it's somewhat simple to increase the size of your boat, most of the rules stay the same. But as you build bigger cyclers, one will either need bigger rockets or more rockets and then possibly assembly/docking in space, so it's definitely more complicated than making a larger displacement in the water. [0] https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation
      - PaulDavisThe1st 3y ago
        I thought that the whole point of a cycler was to reduce the need for rocket propulsion to a vanishingly small part of the system.
        accrual 3y ago
        That is true. My comment was more about the initial setup of a larger cycler. Larger cyclers will cost exponentially more rocket mass/fuel/complexity than a smaller cycler. But once in orbit, yes, the design reduces overall fuel costs.
      - ben_w 3y ago
        Rocket equation makes faster exponentially difficult; merely heavier scales linearly.