Uranus orbits 2,870,990,000 kilometres (19.218 AU) from the Sun. It is the third largest planet, with a diameter of 51,118 kilometres, and weighing 8.683e25 kilograms, is the fourth heaviest planet in our Solar System.
Uranus has only ever been visited by one of our spacecraft, which was Voyager 2 on Jan 24 1986. The strangest thing about Uranus is that while most planets spin on an axis almost perpendicular to the plane of the ecliptic , Uranus' axis is pretty much parallel to the ecliptic. So when Voyager 2 passed Uranus in 1986, Uranus' South Pole was pointed at the Sun. This results in Uranus' Polar Regions receiving more sunlight than its equatorial regions. However Uranus' equator is till hotter than its poles. The reason for this is unknown.
The composition of Uranus is mostly rock and various ices, with approximately 15% hydrogen and some helium. It seems that Uranus does not have a rocky core like Jupiter or Saturn and that the material there is more or less evenly distributed. While Uranus' atmosphere is 83% hydrogen, 15% helium and 2% methane.
The reason behind Uranus' strange blue colour is the result of a chemical reaction in its atmosphere. The methane in the upper atmosphere absorbs any right light and so Uranus seems blue when viewed normally. It is believed that there are coloured bands (like Jupiter's) hidden just below the blue layer of the atmosphere.
Uranus is also odd in the fact that its magnetic field is not centred on the centre of the planet and is inclined 60º to its axis.
Currently, Uranus has 21 satellites and 11 known rings.