Ariel

Series of six UK satellites launched by NASA between 1962 and 1979. The most significant was Ariel 5 in 1974, which made a pioneering survey of the sky's X-ray wavelengths.

Ariel

Term signifying ‘lion of God’ or ‘altar of God’; in the book of Isaiah, in the Bible, it is applied to Jerusalem. In later Jewish times the name is given to a water spirit.

One of the fallen spirits in John Milton's Paradise Lost bears this name. He also appears in Alexander Pope's Rape of the Lock and Shakespeare's Tempest.

Ariel

In astronomy, innermost of the five major moons (or satellites) of the planet Uranus. It was officially discovered in 1851 by English astronomer William Lassell, but was probably seen by Russian astronomer Otto Struve four years earlier.

Ariel is thought to consist primarily of water ice. It has an estimated diameter of 1,160 km/721 mi and orbits Uranus at an average distance of 191,020 km/118,432 mi with a period (the time it takes to circle the planet) of 2.52 days. Images from the Voyager 2 probe, taken in January 1986, show craters and channels that may be caused by volcanic activity.