Uranus:
Uranus is the 7th planet in our solar system. It lies about 1.79 billion miles from the Sun, or about 215,000 planet Earths away (pretty hard to imagine that but it's true!). Uranus has a diameter of 31,763 miles, making it about 4 times wider than Earth. Uranus is labeled as a gas giant planet, similar to Jupiter and Saturn, however with some very distinct differences.
Uranus has a diameter that is almost exactly four times that of Earth's.
Uranus, and its nearly twin planet Neptune, are often grouped into a relatively new type of planet called ice giants. This new distinction between normal gas giants like Jupiter and Saturn (both of which are comprised of mostly helium and hydrogen) has to do with their internal structure.
Uranus, unlike Jupiter and Saturn, has an internal structure composed of three main layers. The inner most layer is composed of similar elements that make up the Earth (mostly silicate rocks and iron). The middle layer or mantle is composed of an amazing combination of water, ammonia, and methane ices. This layer is what gives Uranus and Neptune their new classifications. Because of the extremely cold temperatures when you get really far away from the sun, coupled with the immense pressures inside of Uranus, you get crazy compounds that scientists really have no reference for on Earth. They are described as ices by Nasa scientists however their actual structure is a bit of a mystery. Some scientists have gone so far as to call the mantle of Uranus an ocean, however much more research is needed in order to prove such hypothesis. The outer most layer is composed of helium and hydrogen, just like Jupiter and Saturn, however the abundant presence of methane is what differs Uranus and Neptune from the other gas giants.
Unfortunately for me and you, not all that much is known about Uranus as only one mission has ever gone to the planet, Voyager 2, way back in 1986. This mission was also only a flyby, but it did give us the first detailed images of Uranus and enlightened the world to the coolest thing about Uranus.
Uranus with its rings and a rare surface cloud
Notice anything about the above picture? Well, despite what you may have guessed, it isn't the rings themselves, but their orientation. Uranus is thus far the only planet discover that rotates almost completely on its side. It also rotates the opposite way, just like Venus. Scientists have been completely baffled by this for years, however the only real explanation is that at some point early on in the planet's history, an Earth sized object must have smashed into it, distorting Uranus' orientation and rotation. This massive impact is believed to have taken place during the same chaotic period in our early solar system that scientists believe formed our moon (although this will probably never be confirmed). The simple fact of the matter is that Uranus is mostly a mystery, due to its awesome distance from the Sun, making it wildly expensive to send things out to take a look. Hopefully one day something like Cassini (the satellite currently in orbit around Saturn) will grace the Uranus system.
In case you were wondering, Uranus has 27 moons, all of which are named after characters from the writings of Shakespeare and Alexander Pope. None of the moons are very significant and not very much is known about them. The largest of them, Titania, has a diameter of only 981 miles.
The above image shows Uranus' biggest moons in relation to the size of their host planet. From left to right: Puck, Miranda, Ariel, Umbriel, Titania, and Oberon.
I really wish Uranus was more interesting but until more research is done, there isn't much else we can know.
