Surface and atmosphere
Most scientists believe Saturn is a giant ball of gas that has no solid surface. However, the planet seems to have a hot solid inner core of iron and rocky material. Around this dense central part is an outer core that probably consists of ammonia, methane, and water. A layer of highly compressed, liquid metallic hydrogen surrounds the outer core. Above this layer lies a region composed of hydrogen and helium in a viscous form. The hydrogen and helium become gaseous near the planets surface and merge with its atmosphere, which consists chiefly of the same two elements.
A dense layer of clouds covers Saturn. Photographs of the planet show a series of belts and zones of varied colors on the cloud tops. This banded appearance seems to be caused by differences in the temperature and altitude of atmospheric gas masses.
The plants and animals that live on Earth could not live on Saturn. Scientists doubt that any form of life exists on the planet.
Temperature
The tilt of Saturns axis causes the sun to heat the planets northern and southern halves unequally, resulting in seasons and temperature changes. Each season lasts about 7 1/2 Earth years, because Saturn takes about 29 times as long to go around the sun as Earth does. Saturns temperature is always much colder than Earths, because Saturn is so far from the sun. The temperature at the top of Saturns clouds averages -285 degrees F .
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