Uranus is the only giant planet whose equator is nearly at right angles to its orbit. A collision with an Earth-sized object may explain Uranus' unique tilt. Nearly a twin in size to Neptune, Uranus has more methane in its mainly hydrogen and helium atmosphere than Jupiter or Saturn. Methane gives Uranus its blue tint.
Featured Mission: Voyager 2
Most of what we know about Uranus came from Voyager 2's flyby in 1986. The spacecraft discovered 10 additional moons and several rings before heading on to Neptune.
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