Sandra Lee

I can stay in the bath for, well, the longest has been seven or eight hours. I get completely set up with my laptop so I can watch 'The Sopranos,' put out some scented candles, music. I have a towel nearby so I can dry my hand to change the music or the TV. I make a little heaven for myself. And then I just refill and refill.

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.