Saturn
Saturn is the sixth planet from the Sun and the second-largest in
the Solar System, after Jupiter. It is a gas giant with an average
radius of about nine and a half times that of Earth. It only has
one-eighth the average density of Earth.
Despite consisting largely of hydrogen and helium, most of
Saturn's mass is not in the gas phase, because hydrogen becomes a
non-ideal liquid when the density is above 0.01g/cm3, which is
reached at a radius containing 99.9% of Saturn's mass.
The outer atmosphere of Saturn contains 96.3% molecular hydrogen
and 3.25% helium by volume. The planet's most famous feature is
its prominent ring system, which is composed mostly of ice
particles with a smaller amount of rocky debris and dust.
