QUESTION:
I think Titan is a better place looking for life than Mars, as it has water.
Can life evolve in such satellites (moons) of a planet?

ANSWER from Jack Farmer on July 25, 1997:
While Titan may contain one of the richest stores of organic molecules in
the Solar Sytem, it is unlikely that these compounds have nurtured the
origin of life on the surface of that moon of Saturn because of the lack of
liquid water. The surface temperature of Titan is about minus 290 degrees
Fahrenheit so that all the water there is locked up as ice.  The interest in
Titan is more in its atmospheric chemistry which may reveal interesting
things about prebiotic chemistry of interest for origin of life studies.

Nevertheless, the icy satellites of the outer planets do in fact hold much
interest in the search for life beyond the Earth because of the possibility
that they may contain liquid water in the subsurface at depths where heat
and pressure allow liquid water to exist. In this context, Europa is of
special interest because recently obtained Galileo images suggest there may
actually be a subsurface ocean beneath the icy crust of this Galilean
satellite.

Jack D. Farmer, PhD.
NASA Ames Research Center
http://exobiology.arc.nasa.gov