Uranus was the first planet to actually be "discovered." It was found in 1781 by a famous astronomer named William Herschel. He used a homemade telescope, and at first thought he discovered a comet. Uranus has a total of 15 satellites (moons). The five main ones are Miranda, Ariel, Umbriel, Titania, and Oberon. Uranus is the seventh planet from the Sun and is the third largest. Its average distance from the Sun is 1,784 million miles. The equatorial diameter of Uranus is 31,763 miles, the polar diameter is 31,035 miles. The length of one year on Uranus is 84.01 earth years. In an average person's life, he/she can live through one Sun-Uranus orbit. The length of one day on Uranus is 17.9 earth hours. The average surface temperature usually stays around -346 degrees fahrenheit. In weight, Uranus is 14.53 times heavier than Earth. The average density of Uranus is 1.29 grams per cubic centimeter.
At its brightest, Uranus can be glimpsed with the naked eye if you know just where to look. Like the other planets, though, it appears to change its position among the stars. It looks like a star, although it does not twinkle.
Like Saturn and Jupiter, Uranus has rings. They were first discovered from Earth in 1977. Then, in 1986, the Voyager space probe photographed and measured them. Mostly, the rings are made up of dust. The outer ring's dust is particularly dark.
The atmosphere of Uranus is mostly hydrogen gas, with helium and tiny amounts of other gases. The upper atmosphere contains a lot of helium, which makes Uranus look blue-green. The planet has a small, rocky core.
Uranus moves through space at about 7km (4 1/4 miles) per second.
Uranus Fun Facts
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