Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass two and a half times that of all the other planets in the Solar System combined, but a little less than one-thousandth the mass of the Sun. Jupiter is the third-brightest natural object in the Earth's night sky after the Moon and Venus. It has been observed since pre-historic times and is named after the Roman god Jupiter, the king of the gods, because of its massive size.
