Uranus

Uranus is the seventh planet from the sun. It is a gas giant. It is the first planet discovered that was not known in ancient times. Sir William Herschel discovered the planet in 1781, annd orignally called it Georgium Sidus (George's Star) in honour of King George III of England. French astronomers began calling it Herschel before German [Johann Bode]? proposed the name Uranus.

• Mass: 8.683*10²⁵ kg (15 earth masses)
• Diameter: 51,118 km at the equator
• Surface Area: 8,130,000,000 km²
• Orbital period: 84 years
• Orbital radius: 2,870,990,000 km (19.218 AU)
  • Aphelion: 3,004,000,000 km
  • Perihelion: 2,735,000,000 km
• Axial tilt: 82.1°
• Atmospheric components: 85% hydrogen, 15% helium

Uranus has twenty or so moons. The first two were discoverd by Herschel in 1787, and named, by his son, after characters from Shakespeare's A midsummer night's dream, as Titania and Oberon. Two more moons discovered by [William Lassell]? in 1851 were named Ariel and Umbriel; G. Kuiper discovered the moon Miranda in 1948. All moons of Uranus are named after characters from Shakespeae or [Alexander Pope]?.

The flyby of the [Voyager 2]? space probe in January of 1986 led to the discovery of another 10 moons. Six additional moons have been discovered by telescope since the Voyager flyby. Uranus has a faint ring system.

The reason for Uranus' extreme axial tilt, almost ninety degrees, is not known.

Moons (in order of ditance from Uranus):

• Cordelia?
• Ophelia?
• Bianca?
• Cressida?
• Desdemona?
• Juliet?
• Portia
• Rosalind?
• Belinda?
• 1986U10 -awaiting confimation and naming
• Puck
• Miranda
• Ariel
• Umbriel
• Titania
• Oberon
• Caliban?
• Stephano?
• Sycorax
• Prospero?
• Setebos?

Solar system:
Sun - Mercury - Venus - Earth - Mars - Asteroids - Jupiter - Saturn - Uranus - Neptune - Pluto - Comets