Uranus Artwork showing Uranus as seen from Miranda one of its moons Like Jupiter Saturn and Neptune Uranus is a gas giant with an atmosphere mainly composed of hydrogen and helium The atmosphere of the planet occupies about of its radius and overlies an ocean of water ammonia and methane at very high pressure million kiloPascals and temperature Kelvin Miranda is composed of rock and water ice It has a diameter of kilometres km and a mean distance from Uranus of about km Its surface has a surprising range of features including ridges impact craters with diameters up to km and canyons as deep as km
