Exploratour - Life in the Solar System
The environment of the moons, with the exception of Io, and Titan, is one of no atmosphere and no pressure. No atmosphere means there is nothing to even out the warming of the surface by the sun. It is either burning hot, or freezing cold. No pressure means that lifeforms have to have the special exraterrestrial ability to hold their bodies together without the air pressing down. (Recall what happened in the movie Total Recall when the people were thrown outside into the environment of Mars).
This is page 13 of 20
This is page 13 of 20