Uranus

Seventh planet from the Sun and one of the four gas giants in our solar system. It was discovered in 1781 by William Herschel. Its atmosphere consists primarily of hydrogen and helium and appears bluish with a greenish tinge. The volume of the planet is some 67 times greater than that of the Earth and a mass that is 14.7 times greater.

In 1977 it was discovered that like Saturn Uranus has a ring system which stretches 51,300km from the planet's centre. There are also 17 moons in orbit around Uranus, the two largest of which, Oberon and Titania, where discovered by Herschel in 1787.

Uranus is unique amongst the planets in that it possesses a tilt and orbits the Sun on its back.