Saturn

Saturn synbol

Saturn is the sixth planet from the sun and the second largest from the sun. In Roman mythology Saturn is the god of the harvest. Saturn is also the root of the English word "Saturday". Saturn has been known since prehistoric times. Galileo was the first to observed it with a telescope in 1610, he noted its odd elongated appearance.

				Saturn is the least dense of all the planets, its specific gravity is less than that of water. If Saturn were put in a bathtub full of water, it would float! Like Jupiter, Saturn is about 75% hydrogen and 25% helium with traces of water, methane, ammonia and rock. Saturn's interior is similar to Jupiter's consisting of a rocky core, a liquid metallic hydrogen layer and a molecular hydrogen layer. Traces of various ices are also present. The interior of Saturn is hot and it radiates more energy into space than it receives from the Sun.

Saturn has two prominent rings, and a third, outer, much fainter ring. The large gap between the A and B rings is known as the Cassini division(after the probe that discovered it)and the much fainter gap between B and C rings is the Encke division. The rings of Saturn are unlike the rings of the other planets, these rings are very bright. Though they look continuous from the earth, the rings are actually calm particles in an independent orbit. They range in size from a centimeter or so to several meters. The ring particles seem to be composed primarily of water ice, but they may also include rocky particles with icy coatings. The origin of Saturn's rings are unknown. Scientists say they could be remnants of an annihilated moon system. They could have just been there since the planet was formed.

Saturn has 18 named moons, of which Titan is the second largest in the Solar System, after Jupiter's moon Ganymede. Titan is also the only satellite known to have an atmosphere. The other moon are made up of rock and ice. Of the moons for which rotation rates are known, all but Phoebe and Hyperion rotate synchronously. The three pairs (Mimas, Tethys), (Enceladus, Dione), and (Titan, Hyperion) interact gravitationally in such a way as to maintain stable relationships between their orbits. In addition to the 18 named satellites, at least a dozen more have been reported and given provisional designations but it is now unluckily that any of these exist..