4 ms·

Unless we get serious about exploring the outer planets, then fusion will be a must have.

• ncmncm 5y ago
  But not Tokamak fusion. That is a dead end. ITER steals the funding that might otherwise have got aneutronic FRC fusion working by now.
  • mlindner 5y ago
    Correction: But not low-magnetic field Tokamak. High magnetic field Tokamak are a lot smaller and could fit on a large spacecraft. They're room sized, not skyscraper sized.
    • pfdietz 5y ago
      ARC has a mass of 7,190 tonnes (not including generators or radiators). This is about the mass of three US WW2 destroyers. It's not room sized; the thing is something like 20m tall (once you include the support structure). https://arxiv.org/pdf/1409.3540.pdf https://arxiv.org/pdf/1409.3540.pdf A 190MW(e) fission reactor would be considerably smaller. There is really no use case for DT fusion in space, especially if they have to make their own tritium.
      • formerly_proven 5y ago
        > in space Pretty much all space-faring SciFi, including "hard scifi", is basically garbage that you can toss out the window as far as expectations go. Think things are hard to cool on earth? Space leaves you with radiative cooling only. The least efficient (space x time x cost x performance) type of cooling in the known universe. Internally-powered propulsion in spacecraft is never going to happen with thermodynamics around.
    • ncmncm 5y ago
      Anything involving neutron capture is a dead end, for spacecraft especially.