Lichen Can Survive in Space: Space Station Research Sheds Light On Origin of Life

http://www.sciencedaily.com/releases/2012/06/120623145623.htm

ScienceDaily (June 23, 2012) — You can freeze it, thaw it, vacuum dry it and expose it to radiation, but still life survives. ESA's research on the International Space Station is giving credibility to theories that life came from outer space -- as well as helping to create better sunscreens.

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Living organisms surviving in open space supports the idea of 'panspermia' -- life spreading from one planet to another, or even between solar systems.

It seems possible that organisms could colonize planets by hitching rides on asteroids. ESA is probing this intriguing theory further on future Station missions with different samples.