Moon + Mars Colonization... in caves?

[Steven Johnson]

I guess this means that NASA will be seeking experienced cavers for future settlements?

http://news.discovery.com/space/subterr ... nists.html

http://science.slashdot.org/story/10/07 ... nderground

[JR-Orion]

"The tunnels would shield colonists from micrometeorites, lethal X-ray blasts from our petulant sun, and cosmic rays from the galaxy. Temperatures inside the tubes would remain a constant -35 degrees Fahrenheit."

Sounds good to me. Might as well take advantage of what nature has already provided. You'd think it might be cheaper than building an above ground complex strong enough to be safe and deal with the +250 / -250 degree day night cycle.