Saturn
Saturn Sixth planet from the Sun and second-largest in the Solar System. Viewed through a telescope, it appears as a flattened golden yellow disk encircled by white rings. The rings are made up of particles ranging from dust to objects a few metres in size, all in individual orbits. The main rings are only a kilometre or so thick. Voyager space probes revealed the ring system to be made up of thousands of separate ringlets. Saturn has an internal heat source, which probably drives its weather systems. It is assumed to be composed predominantly of hydrogen, and to have an iron-silicate core about five times the Earth's mass, surrounded by an ice mantle of perhaps twenty Earth masses. The upper atmosphere contains 97% hydrogen and 3% helium, with traces of other gases.
http://lpl.arizona.edu/nineplanets/nineplanets/saturn.html; http://wr.usgs.gov
http://lpl.arizona.edu/nineplanets/nineplanets/saturn.html; http://wr.usgs.gov
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Saturn
