"Uranus, one of the giant planets, is the seventh planet from the Sun, sometimes visible to the naked eye. It has 27 satellites, ring system, and an axis of rotation almost lying in the plane of the orbit. Mean distance from Sun: 2870 million km; period of revolution around sun: 84 years; period of axial rotation: 17.23 hours; diameter and mass: 4 and 14.5times that of earth respectively."