Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. It is a gas giant with an average radius of about nine-and-a-half times that of Earth.[26][27] It has only one-eighth the average density of Earth, but is over 95 times more massive.[28][29][30]
Saturn's interior is thought to be composed of a rocky core, surrounded by a deep layer of metallic hydrogen, an intermediate layer of liquid hydrogen and liquid helium, and finally, a gaseous outer layer. Saturn has a pale yellow hue due to ammonia crystals in its upper atmosphere. An electrical current within the metallic hydrogen layer is thought to give rise to Saturn's planetary magnetic field, which is weaker than Earth's, but which has a magnetic moment 580 times that of Earth due to Saturn's larger size. Saturn's magnetic field strength is around one-twentieth of Jupiter's.[31] The outer atmosphere is generally bland and lacking in contrast, although long-lived features can appear. Wind speeds on Saturn can reach 1,800 kilometres per hour (1,100 miles per hour).
The planet has a prominent ring system, which is composed mainly of ice particles, with a smaller amount of rocky debris and dust. At least 146 moons[32] are known to orbit the planet, of which 63 are officially named; this does not include the hundreds of moonlets in its rings. Titan, Saturn's largest moon and the second largest in the Solar System, is larger (while less massive) than the planet Mercury and is the only moon in the Solar System to have a substantial atmosphere.[33]
Name and symbol
Saturn is named after the Roman god of wealth and agriculture and father of Jupiter. Its astronomical symbol (♄) has been traced back to the Greek Oxyrhynchus Papyri, where it can be seen to be a Greek kappa-rho ligature with a horizontal stroke, as an abbreviation for Κρονος (Cronus), the Greek name for the planet ().[34] It later came to look like a lower-case Greek eta, with the cross added at the top in the 16th century to Christianize this pagan symbol.
The Romans named the seventh day of the week Saturday, Sāturni diēs ("Saturn's Day"), for the planet Saturn.[35]
Physical characteristics
Saturn is a gas giant composed predominantly of hydrogen and helium. It lacks a definite surface, though it is likely to have a solid core.[36] Saturn's rotation causes it to have the shape of an oblate spheroid; that is, it is flattened at the poles and bulges at its equator. Its equatorial radius is more than 10%
Caption this Meme
