Uranus
Uranus, the third largest planet in the solar system. It has a diameter of 31,765 miles (51,118 kilometers) which is about four times the diameter of Earth. Although Uranus is much larger than Earth, its surface gravity is less than the surface gravity on Earth. This is because Uranus is made up of gases and is not solid like Earth. This makes Uranus very light for its size. The surface gravity on Uranus is about 86% of the surface gravity on Earth, so if you weigh 100 pounds on Earth, you would weigh 86 pounds on Uranus. Uranus is more than 19 times farther from the sun than Earth is. Uranus is an average distance of 1,783,939,400 miles or 2,870,972,200 kilometers from the sun.
Because its orbit is elliptical, its distance from the sun changes depending on where it is in its orbit. The closest Uranus gets to the sun is 1,699,800,000 miles or 2,735,560,000 kilometers. The farthest it gets from the sun is 1,868,080,000 miles or 3,006,390,000 kilometers. Uranus’ atmosphere is made up of hydrogen, helium and methane. The methane in Uranus’ upper atmosphere absorbs the red light from the sun but reflects the blue light from the sun back into space. This is why Uranus appear blue.
Uranus revolves or orbits around the sun once every 84 Earth years, or once every 30,687 Earth days. Uranus travels at an average speed of 15,290 miles per hour or 24,607 kilometers per hour in its orbit around the sun. Uranus has 9 brighter rings as well as several fainter rings. Some of the larger rings are surrounded by belts of fine dust. The outermost ring is made up of ice boulders several feet across. The other rings are made up mainly of icy chunks darkened by rocks. The rings are thin, narrow, and dark compared to the rings of other planets. They are actually so dark that they reflect about as much light as charcoal. They appear brighter in the image to the left because the image has been artificially brightened by a computer. The rings may have been formed by the break up of a small moon.
The planet Uranus was discovered by William Herschel on March 13, 1781. He discoverd Uranus while surveying stars in the night sky using a telescope that he had built himself. Herschel noticed that one of these “stars” seemed different, and after observing it many more times, noticed that it orbited the sun. He calculated that Uranus had an orbit that was about 18 times farther from the sun than Earth. Herschel also discovered two of the moons of Uranus (Titania and Oberon).
