Uranus is made up mostly of hydrogen and helium gases, layered on top of a liquid core. It is this icy material – water, methane and ammonia – located at the interior of the planet that gives Uranus its density. The outer layers are clouds, which reflect sunlight and give the planet its blue color.
Uranus has an unusual rotation axis that runs from its top to its bottom, rather than from side to side like all the other planets. Scientists hypothesize that this is the result of an interplanetary collision. This unusual axis has interfered with the planet's magnetic field, throwing into question which is the true north pole. It has 13 rings, all of which are perpendicular to its orbit.
Scientists know of 27 moons orbiting Uranus, all of which have names paying homage to writers William Shakespeare and Alexander Pope. Perhaps the most popular moon is Miranda, a patchwork of peaks and valleys. Uranus, first discovered in 1781 by William Herschel, orbits the Sun once every 84 years. Even the seasons are long, spanning two decades.Learn more about Planets