[snowsislander]

I wish they could figure out a way to cut a core sample and get it home. They could pick a dozen random sites on Mars, and a dozen asteroids at random, and see what this stuff is made of.

If all goes well, (and that is a big "if", it is an extraordinarily ambitious mission), Japan's Hayabusa should be back with asteroid samples (not a core, just a small amount from the surface) in 2007 -- it is now on its way to the asteroid belt to attempt to rendezvous with Itokawa, and it is driven by a microwave ion propulsion drive. It just did a swing-by of Earth back in May of this year.

[marron]

Wow. Even that sample could tell us a lot, I think.