ion engine was RE: [extropy-chat] Saving the Hubble

[Spike]

> And by the way, this business of using xenon as the
> reaction mass, can't we go with something a mite less
> exotic, like, say, iron?  (I'm looking ahead to those
> asteroids...)  What's the story?
> 
> Best, Jeff Davis

No.  Ideally in an ion engine you want your working
fluid to be as dense as possible.  Radon would be even
better if not for that radioactivity problem.  If we 
used iron as a propellant, we would waste too much 
energy in vaporizing the stuff.

spike