Uranus is the only planet which lies on its side as it revolves around the Sun. Because it is at the limit of naked eye visibility, Uranus was unknown until William Herschel discovered it with a telescope in 1781. The rings were revealed when they occulted a star in 1977.

Uranus and Neptune are sometimes referred to as the "ice giants", their compositions being dominated by water, ammonia (NH₃), methane (CH₄)' and some 'rock" composed of silicates and metals. They have a hydrogen/helium atmosphere which is thought to have a mass of around 1 - 3 times the mass of the Earth.

The image of Uranus' moon Miranda is a computer-assembled mosaic of images obtained on Jan 24, 1986 by the Voyager 2 spacecraft. Miranda is the innermost and smallest of the five major Uranian satellites, just 480 km (300 mi) in diameter. Nine images were combined to obtain this full-disc, south polar view, which shows the varying geologic provinces of Miranda. Miranda's surface consists of two strikingly different major types of terrain. One is an old, heavily cratered, rolling terrain with relatively uniform albedo (reflectivity). The other is a young, complex terrain characterized by sets of bright and dark bands, scarps and ridges - features found in the regions at right and left and in the distinctive "chevron" feature below and right of center.