MNN Galleries

Life's lucky 7: The places most likely to harbor aliens

By: Bryan Nelson on Feb. 17, 2010, 12:20 p.m.

Photo: Wiki Commons/public domain

2 of 9


Mars is the most Earth-like planet in our solar system, and there's an extremely high probability that life either exists or has existed there before. The evidence is overwhelming. Life's most important necessity, liquid water, is widely believed to have flowed across the planet in the past, and recent photographs from the Mars Global Surveyor show evidence of recent flows (within the last 10 years) of a liquid on the Red Planet's frigid surface.