Wikipedia:Today's featured article/October 12, 2017
Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. Named after the Roman god of agriculture, it is a gas giant with an average radius about nine times that of Earth. Although it has only one-eighth the average density of Earth, it is over 95 times more massive. A core, probably iron–nickel and rock, is surrounded by a deep layer of metallic hydrogen, an intermediate layer of liquid hydrogen and liquid helium, and a gaseous outer layer. Ammonia crystals give the upper atmosphere a pale yellow hue. Electrical current within the metallic hydrogen layer is thought to give rise to the planetary magnetic field. Wind speeds can reach 1,800 km/h (500 m/s), higher than on Jupiter, but not as high as on Neptune. A prominent ring system with nine continuous main rings and three smaller arcs is composed mostly of ice particles, with some rocky debris and dust. Saturn has hundreds of moonlets and at least 62 moons, including Titan, the second-largest moon in the Solar System and the only one with a substantial atmosphere. (Full article...)
Part of the Solar System featured topic.