Roy Orbison

I think what's going to hurt the Republicans enormously is the extremist position of Mitt Romney on the immigration issue and states like New Mexico, states like Colorado, Nevada, Arizona - and I think it's going to be the margin of victory for President Obama, a very narrow victory.

Supplying fuel for a Mars expedition from the lunar surface is often suggested, but it's hard to make it pay off - Moon bases are expensive, and just buying more rockets to launch fuel from Earth is relatively cheap.