6 ms·

proton-boron fusion producing high speed (~ 0.03c) alpha particles reflected by magnetic field http://en.wikipedia.org/wiki/Fusion_power#p-11B_fuel_cycle http:

proton-boron fusion producing high speed (~ 0.03c) alpha particles reflected by magnetic field http://en.wikipedia.org/wiki/Fusion_power#p-11B_fuel_cycle http://en.wikipedia.org/wiki/Fusion_power#p-11B_fuel_cycle It will let us to comfortably get to the solar system planets and to launch first multi-decade travel to the nearest star. (Google for Bussard)

sorbus 15y ago
There's also always the Orion drive - basically dropping nuclear bombs out of the back of a ship and riding on the blast. Do you know how it and the Bussard Ramjet (which I think is what you meant) compare in terms of mass needed to run? Of course, a Ramjet would probably be much better for long missions, since it gives you a source of power as well as not requiring carrying reaction mass, which avoids running out of fuel.
- VladRussian 15y ago
  Bussard's ramjet is too far fetched still. I meant more along the lines of http://www.emc2fusion.org/2006-9%20IAC%20Paper.pdf http://www.emc2fusion.org/2006-9%20IAC%20Paper.pdf and http://www.ibiblio.org/lunar/school/InterStellar/Explorer_Class/Bussard_Fusion_systems.HTML http://www.ibiblio.org/lunar/school/InterStellar/Explorer_Cl... The EMC2 is (was) his corporation that gets [though very small compare to other causes government spends money on] real funding and making real progress today, just as we speaking :) though i'd not discount the Z-pinch (Sandia) approach and think that ultimately working system may be a combination of these 2 approaches. The Z-pinch, dense plasma focus and other similar dynamic (inertial) confinement approaches is, in principle, the Orion, only with very small "bombs".
- InclinedPlane 15y ago
  Bussard ramjets are non-starters. Firstly, as it turns out the drag from the ramjet would be much higher than the thrust generated by the fusion reaction. Secondly, a pure Bussard drive would be hugely difficult because proton-proton fusion is enormously challenging and would require very, very high temperatures to occur in a practical amount of time within a rocket.
curt 15y ago
Don't know why more research hasn't been done on Boron fusion. Since it gives off an electron you don't need any turbines or heavy equipment just a transformer. Instead we spend billions on H2 H3 fusion. Makes no sense to me.
- VladRussian 15y ago
  except for D/T (and D/D), most of other fusion reactions which don't involve exotic components (like He3) don't seem to be confine-able by the mainstream magnetic confinement (tokamak). The inertial confinement is starting to come back and with it the promise of the other reactions.
- mattheww 15y ago
  It's unclear whether it's possible to reach a breakeven point.
  - jackpirate 15y ago
    That's true for any controlled fusion reaction.
    - VladRussian 15y ago
      the lowest upper bound we have is 5-10Kt thermonuclear bomb. I.e. we do know that using at least one type of confinement - inertial - with X rays as driver it is possible to get energy-net-positive on the scale of such a small bomb. On the other side, ie. the lower bound - the Z machine at Sandia is generating X rays with power enough to drive the reaction similar to how the fusion is driven by X rays in the H bomb, just on the much smaller scale, and we do know that scaling it up or the other existing designs, like the tokamak or polywell or laser driven device like NIF, does increase the reaction efficiency. Somewhere between is the practical energy-net-positive reactor. It can be order or 2 of magnitude bigger than ITER - well, the modern coal burning or nuclear plant is several orders of magnitudes bigger than the campfire of the cavemen where it started from.
- InclinedPlane 15y ago

sorbus 15y ago

There's also always the Orion drive - basically dropping nuclear bombs out of the back of a ship and riding on the blast. Do you know how it and the Bussard Ramjet (which I think is what you meant) compare in terms of mass needed to run? Of course, a Ramjet would probably be much better for long missions, since it gives you a source of power as well as not requiring carrying reaction mass, which avoids running out of fuel.

VladRussian 15y ago
Bussard's ramjet is too far fetched still. I meant more along the lines of http://www.emc2fusion.org/2006-9%20IAC%20Paper.pdf http://www.emc2fusion.org/2006-9%20IAC%20Paper.pdf and http://www.ibiblio.org/lunar/school/InterStellar/Explorer_Class/Bussard_Fusion_systems.HTML http://www.ibiblio.org/lunar/school/InterStellar/Explorer_Cl... The EMC2 is (was) his corporation that gets [though very small compare to other causes government spends money on] real funding and making real progress today, just as we speaking :) though i'd not discount the Z-pinch (Sandia) approach and think that ultimately working system may be a combination of these 2 approaches. The Z-pinch, dense plasma focus and other similar dynamic (inertial) confinement approaches is, in principle, the Orion, only with very small "bombs".
InclinedPlane 15y ago
Bussard ramjets are non-starters. Firstly, as it turns out the drag from the ramjet would be much higher than the thrust generated by the fusion reaction. Secondly, a pure Bussard drive would be hugely difficult because proton-proton fusion is enormously challenging and would require very, very high temperatures to occur in a practical amount of time within a rocket.

curt 15y ago

Don't know why more research hasn't been done on Boron fusion. Since it gives off an electron you don't need any turbines or heavy equipment just a transformer. Instead we spend billions on H2 H3 fusion. Makes no sense to me.

VladRussian 15y ago
except for D/T (and D/D), most of other fusion reactions which don't involve exotic components (like He3) don't seem to be confine-able by the mainstream magnetic confinement (tokamak). The inertial confinement is starting to come back and with it the promise of the other reactions.
mattheww 15y ago
It's unclear whether it's possible to reach a breakeven point.
- jackpirate 15y ago
  That's true for any controlled fusion reaction.
  - VladRussian 15y ago
    the lowest upper bound we have is 5-10Kt thermonuclear bomb. I.e. we do know that using at least one type of confinement - inertial - with X rays as driver it is possible to get energy-net-positive on the scale of such a small bomb. On the other side, ie. the lower bound - the Z machine at Sandia is generating X rays with power enough to drive the reaction similar to how the fusion is driven by X rays in the H bomb, just on the much smaller scale, and we do know that scaling it up or the other existing designs, like the tokamak or polywell or laser driven device like NIF, does increase the reaction efficiency. Somewhere between is the practical energy-net-positive reactor. It can be order or 2 of magnitude bigger than ITER - well, the modern coal burning or nuclear plant is several orders of magnitudes bigger than the campfire of the cavemen where it started from.
InclinedPlane 15y ago