Scientists propose one-way trips to Mars

Two scientists are suggesting that colonization of the red planet could happen faster and more economically if astronauts behaved like the first settlers to come to North America - not expecting to go home.

Schulze-Makuch and Paul Davies, a physicist at Arizona State University, argue that humans must begin colonizing another planet as a hedge against a catastrophe on Earth. They believe the one-way trips could start in two decades.

Both men contend that Mars has abundant resources to help the colonists become self-sufficient over time. They write that the colony should be next to a large ice cave, to provide shelter from radiation, plus water and oxygen.