

About every 30 years or so, it is summer in Saturn's northern hemisphere. The atmosphere warms up some and this does cause some large scale storms which last for a few weeks until the bulk of the rest of the atmosphere tears the storm system apart.
Saturn's atmosphere has nearly the same composition as Jupiter's. It is mostly hydrogen and helium, methane, water vapor and ammonia. The reason Saturn's cloud bands are not as bright as Jupiter is because Saturn has lower temperatures and so the clouds lie lower in the atmosphere. There is also a layer of haze which partly covers the clouds below.
Wind speeds on Saturn are much higher than the winds of Jupiter. Near the equator, winds on Saturn are about 500 m/s. Temperatures in the atmosphere are very cold, much colder than Jupiter. Inside Saturn's cloud tops, the temperature is an average of -180 degrees C (-292 F.)
Saturn's interior is probably very much like Jupiter also. Both are similar to the composition of the Sun. It is possible that Saturn has a rocky core about 20,000 km in diameter and about 20 Earth masses. Above that is most likely a thick layer of liquid hydrogen and a small layer of liquid metallic hydrogen.
Saturn has the lowest density of any of the planets in the solar system. The density is a remarkable 0.7 g/m3. Less dense than water, a Saturn would float if you had a water ocean large enough to sit the planet in!
Copyright © 1997 Kathy A. Miles and Charles F. Peters II