jupiter

Jupiter is the fifth planet from the Sun and the largest in the Solar System. A gas giant, Jupiter's mass is more than two and a half times that of all the other planets in the Solar System combined and slightly less than one one-thousandth the mass of the Sun. Jupiter orbits the Sun at a distance of 5.20 AU (778.5 Gm) with an orbital period of 11.86 years. It is the third brightest natural object in the Earth's night sky after the Moon and Venus and has been observed since prehistoric times. Its name derives from Jupiter, the chief deity of ancient Roman religion. Jupiter was the first planet to form, and its inward migration during the primordial Solar System impacted much of the formation history of the other planets. Hydrogen constitutes 90% of Jupiter's volume, followed by helium, which forms 25% of its mass and 10% of its volume.