URANUS Yep, its really pronounced YOUR-A-NUS. Uranus was discovered by William Herschel, a British astronomer in 1781. Many people had already seen that faint object in the sky but assumed it was only a star. However, Herschel's observance was that it did not behave like a star. He was also responsible for discovering the largest moons of Uranus, Oberon, and Titania.

Uranus is unlike any other planet in that its orbital plane out of sync with the others. Uranus has an axial tilt of 97.9°. To understand this tilt, imagine earth, which has a 23.5° tilt, suddenly spinning out of control and the north and south poles becomes part if the equator and all of the continents still spin around the new equator. Another phenomenom is Uranus' strong magnetic field. Uranus' magnetic field is oriented approximately 59° away from its unusual axis of rotation.

Uranus is covered in a light blue color because of the methane clouds on Uranus' atmosphere. Uranus' atmosphere is mainly composed of hydrogen, helium and methane. Water, as well as ammonia can be found on Uranus. Not unlike Jupiter and Saturn, Uranus also has rings.

These pulses of light proved the existence of a series of rings around Uranus. The rings had blocked the light, thus causing the observed pulses. The particles that make up the rings range from as small as 4 inches (10cm) to 33 feet (10m).

These two pictures of Uranus - one in true color (left) and theother in false color - were compiled from images returned onJanuary 17, 1986, by the narrow-angle camera of Voyager 2. Thespacecraft was 9.1 million kilometers (5.7 million miles) from the planet.  The blue-green color results from the absorption of red light by methane gas in Uranus' deep, cold, and clear atmosphere. The darker shadings at the upper right of the disk correspond to the day-night boundary on the planet.   The picture on the right uses false colors and contrast enhancement to bring out subtle details in the polar region of Uranus.   In this false-color picture, Uranus reveals a dark polar hood surrounded by a series of lighter concentric bands.

SATELLITES

Uranus has seventeen discovered satellites and out of those seventeen, two are currently unnamed. The satellites that orbit Uranus are:

If you don't already know, many of the names are borrowed from names of the characters in William Shakespeare's A Midsummer Nights Dream. Hershel discovered two of the largest moons orbiting Uranus and named them Oberon and Titania from Shakespeare's play. The smallest of them is approximately 16 miles (25km) in diameter and the largest is over 1000 miles (1,610km) wide. The satellite, Miranda, is unusual because it contains such features as grooves and sets of circles. There is also a cliff over 9 miles (15km) high. Titania is the largest of them all and also exhibits craters and fault lines like the other moons.

	This color picture of Oberon, Uranus' outermost satellite,was taken by Voyager 2 on Jan. 22, 1986. At the time, two days before closest approach, the spacecraft was 2.77 million kilometers (1.72 million miles) from the satellite. This image is a computer reconstruction from three frames, exposed with the Voyager narrow-angle camera's orange, blue and green filters. Oberon has a diameter of about 1,600 km (1,000 mi).
	Voyager 2 obtained this color picture of Titania, one of Uranus' two largest satellites, on Jan. 22, 1986. The spacecraft was 3.11 million kilometers (1.93 million miles) from the satellite. This image is a computer reconstruction from three frames, exposed with the Voyager narrow-angle camera's clear, orange,and violet filters. Titania has a diameter of about 1,600 km (1,000 mi.)
	This color photo of Umbriel, the darkest of Uranus' five large moons, was taken by Voyager 2 on Jan. 23, 1986. At the time, the spacecraft was 1.04 million kilometers (650,000 miles) from Umbriel .   Umbriel is characterized by the darkest surface and smallest brightness variations of any of the large satellites of Uranus. Umbriel has a diameter of about 1,200 km (750 mi) and orbits 267,000 km (166,000 mi) from Uranus' center. The satellite's name, from Alexander Pope's "Rape of the Lock," means "dark angel."

Exploration

Uranus was visited only by the voyager 2 in 1986 and passed with 51,000 miles (82,000 km) of Uranus.

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