Heh, I'm a total layman so this could be trivially impossible, but could we not somehow put a fusion reactor into orbit around earth such that its own gravity would contain itself just like a star? Or would that just not be feasible?
Sure, we could trivially make our own star. All we'd need to do is move at least 100 Jupiters worth of mass into close proximity, and voila! Insta-star. That last part is not so trivial though...
The difficulty us mere mortals have with sustained fusion is keeping the reaction from blowing itself apart (as in dissipation, not bomb). Gravity keeps things in check for free, but since gravity is so weak compared to atomic forces, you need an awful lot of it.
Our current containment solutions using electromagnetic forces require a lot of energy to maintain and so far, more than produced from the resulting fusion reaction.
What if we were to combine both methods? Try to put an electromagnetic containment solution into space? Could we possibly find a medium between electromagnetic forces and gravitational forces that would allow us to make it hold together without having to actually have something as massive as a star?
