The Planets- Uranus 1

Once considered one of the blander-looking planets, Uranus (pronounced YOOR un nus) has been revealed as a dynamic world with some of the brightest clouds in the outer solar system and 11 rings. Uranus gets its blue-green color from methane gas above the deeper cloud layers (methane absorbs red light and reflects blue light).

Astronomer William Herschel, who at first believed it to be a comet, discovered Uranus in 1781. This seventh planet from the Sun is so distant that it takes 84 years to complete an orbit.

Uranus is classified as a "gas giant" planet because it has no solid surface. The atmosphere of Uranus is hydrogen and helium, with a small amount of methane and traces of water and ammonia. The bulk (80 percent or more) of the mass of Uranus is contained in an extended liquid core consisting primarily of "icy" materials (water, methane, and ammonia), with higher-density material at depth.

In 1986, Voyager 2 observed faint cloud markings in the southern latitudes blowing westward between 100 and 600 km/hr. In 1998, the Hubble Space Telescope observed as many as 20 bright clouds at various altitudes in Uranus' atmosphere. The bright clouds are probably made of crystals of methane, which condense as warm bubbles of gas well up from deep in the atmosphere of Uranus.

Uranus currently moves around the Sun with its rotation axis nearly horizontal with respect to the ecliptic plane. This unusual orientation may be the result of a collision with a planet-sized body early in the planet's history, which apparently changed Uranus' rotation radically.


Next- Planet Uranus part2