Uranus was the Greek deity of the Heavens, the father of Cronus (Saturn), and the Cyclopes and Titans. This was the first planet to be discovered in modern times. It was accidentally discovered on March 13, 1781 when William Herschel was searching the sky with a telescope. First, he believed it was a comet because it had been observed many times before. (In fact, the earliest record sighting was in 1690 by John Hamsteed.) Herschel named it "Georgium Sidus" in honor of King George III of England because King George was his patron. However others called it "Herschel". Uranus was proposed to conform to the other planetary names because all other planets' names came from classical mythology. However, the name "Uranus" didn't become popular 1850.
On January 24, 1986, Voyager 2 became the first and only (so far) spacecraft to visit Uranus. At the time, the south pole was pointed almost directly towards the sun which caused the poles to receive more sunlight than the regions near the equator. Nonetheless, poles are colder than equator.
In fact, there is an ongoing debate over which is the south pole and which is the north pole!!! Either the plant is tilted a bit over 90 degrees and the planet's spin is normal or the planet is tilted a little less than 90 degrees and the rotation motion is retrograde.
Uranus is composed of mainly rock and various ices with only 15% hydrogen and a little helium. This is quite different from Jupiter and Saturn which are composed primarily of hydrogen. However its core is similar to Jupiter and Saturn's core (not including the liquid metallic envolope). Uranus's core material is almost evenly distributed.
The atmosphere of Uranus is composed of 83% hydrogen, 15% helium, and 2% methane. It has bands of clouds that rapidly blow around rapidly. But the clouds are extremely faint. Uranus' blue color is the result of absorption of red light by methane in the upper atmosphere. There may be colored bands but they are hidden from view.
Like Jupiter, Uranus has rings that are composed of large particles and are dark. There are eleven faint rings that we know of. These rings were the first to be discovered after Saturn's. This was important because we know know that rings are regular feature of planets, and it is not a peculiarity of Saturn.
Voyager 2 discovered 10 more smaller moons in addition to the 5 larger moons we already knew about. It is possible there could be more moons within the moons that we don't know about. The moons get there name from the writings of Shakespeare and Pope. They all have very circular orbits.
Other sites on Uranus--
Site by Regional Planetary Image Facility
Pictures of Uranus and its Satellites
Hot Pictures from Hubble Space Telescope
