Surface Features
Saturn, like Jupiter,
has no surface. What we perceive as a surface is actually the tops of the clouds.
Also like Jupiter,
the highest clouds seen in Saturn's atmosphere appear to be composed of crystals of frozen
ammonia.
Colors on Saturn
The "surface" of Saturn bears many similarities with the surface of Jupiter. There is a banded
structure,
but the color contrast is generally less. This is thought to be because Saturn
is colder than Jupiter (further from the Sun), so it has different chemical
reactions in its atmosphere, leading to different coloration. As noted in the right panel,
chemical reactions producing colored compounds in the atmosphere of Jupiter may simply proceed too slowly
to have much effect in the colder atmosphere of Saturn. There is also a haze layer for Saturn that may
partially mute the colors.
Anticyclonic Cells
There are large anticyclonic (high pressure)
cells in Saturn's atmosphere, apparently driven by the
planet's internal heat source. None are as large as the Great Red Spot on
Jupiter, and they are not as abundant as on Jupiter. The above image is an oval-shaped
red anticyclonic disturbance in Saturn's atmosphere that is about the diameter of the Earth.