An interplanetary trip to Mars could take as little as 10 months, but returning would be virtually impossible -- making the voyage a form of self-imposed exile from Earth unlike anything else in human history.

What would inspire someone to volunteer? We've just found out.

A special edition of the Journal of Cosmology details exactly how a privately-funded, one-way mission to Mars could depart as soon as 20 years from now -- and it prompted more than 400 readers to volunteer as colonists.