8 ms·

As far as I understand there is still some time before humanity becomes interplanetary in any meaningful way, maybe even many generations. And what is going on

by bobl 8y ago

As far as I understand there is still some time before humanity becomes interplanetary in any meaningful way, maybe even many generations. And what is going on so far these days is mostly about not regressing.

leesec 8y ago
Making rockets re-usable is a massive step forward and not about 'not regressing'.
- johannes1234321 8y ago
  In the past we even had space ships, which could start from ground, go to space, do stuff, come back and the could be reused. Having just a rocket isn't that much of an improvement. That said: All the constraints on making it reusable and safe for humans are also a key factor why Space Shuttle was so expensive. With SpaceX's rockets not all parts need to resist the stress of reentry etc.
  - KineticLensman 8y ago
    > In the past we even had space ships, which could start from ground, go to space, do stuff, come back and the could be reused The 're-used' aspect of the Shuttle involved massive re-fits which took months for each vehicle. It was like having to send your car back to the manufacturer for a total rebuild (often including engine change) every time you went for a drive. SpaceX is a massive improvement in this respect.
    - jacquesm 8y ago
      And two expended boosters and an expended fuel tank.
      - HALtheWise 8y ago
        Nitpick: the boosters were reused by parachute splashdown, but it was also really expensive due to (among other things) the corrosiveness of salt water. The External Tank was in fact expended.
        KineticLensman 8y ago
        Each SRB consisted of 11 cylindrical steel sections. After flight and recovery, these were dismantled, refilled with solid rocket fuel as appropriate, and then reconnected to form a new SRB with all of the O-rings, etc. So also a complete rebuild, with reuse occurring at the segment level, not of the whole booster assembly.
  - Robotbeat 8y ago
    Dragons are also reused (although at first, these newer ones will only be reused for cargo flights). Additionally, SpaceX is serious about Starship/BFR. That's fully reusable and will be capable of going to the Moon (or even Mars) and back fully reusably: https://twitter.com/JaneidyEve/status/1102023437206388736 https://twitter.com/JaneidyEve/status/1102023437206388736
- bobl 8y ago
  I doesn't seem clear at this point whether re-usable will be significant for activities beyond earth orbit. Partly the excitement comes from being a workaround for humanities reluctance to spend money on space exploration. Believe what you want, but from what I can find this doesn't seem to be a significant part of what would e.g. make humanity interplanetary. At least not yet.
  - mrtnmcc 8y ago
    If you want to get back from Mars you need a reusable rocket.
    - kbutler 8y ago
      By that definition, the Apollo program had reusable rockets. (Able to climb back out of a gravity well, leave orbit of a large mass, and return to earth). Escape velocity of Mars is less than half Earth's or about double the moon's.
  - amazingman 8y ago
    Overcoming blockers is always significant.
  - rocqua 8y ago
    Getting to orbit is hard, for anything big beyond earth orbit, we'll probably need manufacturing or at least some assembly in orbit. That takes a lot of trips from earth to orbit. Making that more efficient means more resources left for the real exploration.
  - samcday 8y ago
    I dunno if I really follow your logic here. It would be nice if nobody cared about money and we all just worked hard to make everything awesome or whatever. But, we (sadly) don't live in that world. So in this world that we do live in, bringing down the cost of getting things/people from the ground to really really high up in the sky can only be viewed as a step towards becoming multiplanetary.
  - trhway 8y ago
darkerside 8y ago
For all its faults, and it had a few, Three Body Problem by Cixin Liu helped stretch my perspective to be ok with the fact that space travel could be a multigenerational activity even with a quantum leap in technology.

by bobl 8y ago

leesec 8y ago

Making rockets re-usable is a massive step forward and not about 'not regressing'.

johannes1234321 8y ago
In the past we even had space ships, which could start from ground, go to space, do stuff, come back and the could be reused. Having just a rocket isn't that much of an improvement. That said: All the constraints on making it reusable and safe for humans are also a key factor why Space Shuttle was so expensive. With SpaceX's rockets not all parts need to resist the stress of reentry etc.
- KineticLensman 8y ago
  > In the past we even had space ships, which could start from ground, go to space, do stuff, come back and the could be reused The 're-used' aspect of the Shuttle involved massive re-fits which took months for each vehicle. It was like having to send your car back to the manufacturer for a total rebuild (often including engine change) every time you went for a drive. SpaceX is a massive improvement in this respect.
  - jacquesm 8y ago
    And two expended boosters and an expended fuel tank.
    - HALtheWise 8y ago
      Nitpick: the boosters were reused by parachute splashdown, but it was also really expensive due to (among other things) the corrosiveness of salt water. The External Tank was in fact expended.
      - KineticLensman 8y ago
        Each SRB consisted of 11 cylindrical steel sections. After flight and recovery, these were dismantled, refilled with solid rocket fuel as appropriate, and then reconnected to form a new SRB with all of the O-rings, etc. So also a complete rebuild, with reuse occurring at the segment level, not of the whole booster assembly.
- Robotbeat 8y ago
  Dragons are also reused (although at first, these newer ones will only be reused for cargo flights). Additionally, SpaceX is serious about Starship/BFR. That's fully reusable and will be capable of going to the Moon (or even Mars) and back fully reusably: https://twitter.com/JaneidyEve/status/1102023437206388736 https://twitter.com/JaneidyEve/status/1102023437206388736
bobl 8y ago
I doesn't seem clear at this point whether re-usable will be significant for activities beyond earth orbit. Partly the excitement comes from being a workaround for humanities reluctance to spend money on space exploration. Believe what you want, but from what I can find this doesn't seem to be a significant part of what would e.g. make humanity interplanetary. At least not yet.
- mrtnmcc 8y ago
  If you want to get back from Mars you need a reusable rocket.
  - kbutler 8y ago
    By that definition, the Apollo program had reusable rockets. (Able to climb back out of a gravity well, leave orbit of a large mass, and return to earth). Escape velocity of Mars is less than half Earth's or about double the moon's.
- amazingman 8y ago
  Overcoming blockers is always significant.
- rocqua 8y ago
  Getting to orbit is hard, for anything big beyond earth orbit, we'll probably need manufacturing or at least some assembly in orbit. That takes a lot of trips from earth to orbit. Making that more efficient means more resources left for the real exploration.
- samcday 8y ago
  I dunno if I really follow your logic here. It would be nice if nobody cared about money and we all just worked hard to make everything awesome or whatever. But, we (sadly) don't live in that world. So in this world that we do live in, bringing down the cost of getting things/people from the ground to really really high up in the sky can only be viewed as a step towards becoming multiplanetary.
- trhway 8y ago

darkerside 8y ago

For all its faults, and it had a few, Three Body Problem by Cixin Liu helped stretch my perspective to be ok with the fact that space travel could be a multigenerational activity even with a quantum leap in technology.