3 ms·

Space-specific problems are: 1) weightlessness - but people can deal with that, and if needed, I'm sure centrifuges can help; 2) radiation - but large shields c

by avmich 5y ago

Space-specific problems are: 1) weightlessness - but people can deal with that, and if needed, I'm sure centrifuges can help; 2) radiation - but large shields can alleviate this problem; 3) space debris, attacking with large speeds - but we can use radars, shields, plasma clouds to reduce problems from this. With all of these problems large rockets do help.

Robotbeat 5y ago
Space debris is a much worse problem in LEO than anywhere else from here to Mars. Mars’ surface itself at likely landing sites is shielded from all micrometeorites by the atmosphere which burns them up or slows them down to a reasonable terminal velocity (low for micrometeorites, even in the thin Martian atmosphere).
idlewords 5y ago
A centrifuge solves microgravity problems, but no one has ever flown one at human sizes. Seems like a big to-do list item. With cosmic rays, having a large mass of metal around you will actually increase your dose (because of secondary radiation). So you need to figure out shielding that helps more than it hurts. Space is hard.
- avmich 5y ago
  Large rockets still help, even if shielding is not straightforward though.
  - idlewords 5y ago
    Certainly. And if we had a big enough rocket, we could put its fins on earth and the tip on Mars and just climb up the middle.
    - avmich 5y ago
      That all skips the interesting middle values of the problem parameters :) . Seriously, for long time already it's not a rocket science. Existing technologies - with engineering efforts - are capable to bring humans to any point between Mercury and asteroids. We'll likely develop something better, and Solar system would be all reachable without major breakthroughs. Certainly not of the kind "rocket fins on Earth, tip on Mars".
  - Robotbeat 5y ago
    Shielding ESPECIALLY is straightforward, though. The parent was wrong about it being hard.
- Robotbeat 5y ago
  Why the heck would you use metal for shielding when cheap plastic works way better? But anyway, the “shielding increases dose” is only true for a small portion of the thickness curve at the very beginning. Vast majority of the time even metal shielding helps. “Space is hard” is kind of a low-effort mantra. Space radiation shielding really is one of those things that is extremely straightforward to address with mass. Polyethylene, or actually any hydrocarbon solid, works fantastic.

by avmich 5y ago

Robotbeat 5y ago

Space debris is a much worse problem in LEO than anywhere else from here to Mars. Mars’ surface itself at likely landing sites is shielded from all micrometeorites by the atmosphere which burns them up or slows them down to a reasonable terminal velocity (low for micrometeorites, even in the thin Martian atmosphere).

idlewords 5y ago

A centrifuge solves microgravity problems, but no one has ever flown one at human sizes. Seems like a big to-do list item. With cosmic rays, having a large mass of metal around you will actually increase your dose (because of secondary radiation). So you need to figure out shielding that helps more than it hurts. Space is hard.

avmich 5y ago
Large rockets still help, even if shielding is not straightforward though.
- idlewords 5y ago
  Certainly. And if we had a big enough rocket, we could put its fins on earth and the tip on Mars and just climb up the middle.
  - avmich 5y ago
    That all skips the interesting middle values of the problem parameters :) . Seriously, for long time already it's not a rocket science. Existing technologies - with engineering efforts - are capable to bring humans to any point between Mercury and asteroids. We'll likely develop something better, and Solar system would be all reachable without major breakthroughs. Certainly not of the kind "rocket fins on Earth, tip on Mars".
- Robotbeat 5y ago
  Shielding ESPECIALLY is straightforward, though. The parent was wrong about it being hard.
Robotbeat 5y ago
Why the heck would you use metal for shielding when cheap plastic works way better? But anyway, the “shielding increases dose” is only true for a small portion of the thickness curve at the very beginning. Vast majority of the time even metal shielding helps. “Space is hard” is kind of a low-effort mantra. Space radiation shielding really is one of those things that is extremely straightforward to address with mass. Polyethylene, or actually any hydrocarbon solid, works fantastic.