Jupiter

Keywords

Giant planets

Definition

Among the Giant planets, Jupiter is the most massive and also the closest to the Sun; it orbits at 5.2 AU from the Sun. Its mass is 318 times the terrestrial mass and its diameter is 11 times the terrestrial one, which corresponds to a density of 1.31 g/cm³. As the other giant planets, Jupiter is generally believed to have formed in the outer solar system from the accretion of an icy core followed by the collapse of the surrounding nebula, mostly composed of hydrogen and helium. As Jupiter probably formed just beyond the snowline, which marked the condensation of ices in the protosolar disk, its core accretion was fast and the planet could accrete a large amount of protosolar gas, which accounts for its large mass.

Jupiter has a tenuous ring system and many satellites (63 known in 2007), both regular and irregular. The regular satellites were formed in the equatorial plane of the planet after the collapse of the surrounding subnebula. They include the...