Comment Re:Time to moon: 9.2 years (Score 1) 387
Doesn't stability of a LaGrange point - keeping something in it - depend on the point in question? I think you have to fight drift more in L1 through L3, but not so much in L4 and L5.
Wikipedia has some good info on stability: http://en.wikipedia.org/wiki/Lagrange_point#Stability. Or listen to the AstronomyCast episode on LaGrange points: http://www.astronomycast.com/physics/ep-76-lagrange-points/. They describe L1 through L3 as trying to keep a marble on a saddle, but L4 and L5 as keeping a marble in a volcano - hard to get it up there, but somewhat stable once it's there.
It'd be neat if we could keep something in L4 or L5 of the Earth/Moon system, but I agree the costs to and from Earth or Moon are probably still too politically big...
Wikipedia has some good info on stability: http://en.wikipedia.org/wiki/Lagrange_point#Stability. Or listen to the AstronomyCast episode on LaGrange points: http://www.astronomycast.com/physics/ep-76-lagrange-points/. They describe L1 through L3 as trying to keep a marble on a saddle, but L4 and L5 as keeping a marble in a volcano - hard to get it up there, but somewhat stable once it's there.
It'd be neat if we could keep something in L4 or L5 of the Earth/Moon system, but I agree the costs to and from Earth or Moon are probably still too politically big...
