Can I See It?
      You can see Neptune, but you will need at least a pair of binoculars, and probably a telescope. Neptune is no larger than Uranus and is much further away, so it will be even harder to see than the blue-green planet. If you have dark skies and a good view to the southern horizon, you may be able to pick it out with your binoculars. 

 How Big Is It?
      Neptune is about 30 thousand miles in diameter, about four times the size of Earth, which is about 7,600 miles in diameter Neptune and Uranus are almost the same size, but both seem tiny in comparison to mighty Jupiter, which is almost three times as large as either of them. 

 Does It Have Rings? 
      All the gas planets in our solar system have rings, and Neptune is no exception. The Voyager space mission sent pictures to prove it. The rings of Neptune are made up of fairly small, very dark clumps of rock. Scientists believe that most of these clumps are about the size of a compact car. There is also a large amount of dust in the rings. Even though the rings are very faint, they still had a surprise for us. One of the rings has a twist in it! 

 How Many Moons Does It Have?
      Neptune has eight moons that we know about and there may be more. There are only two that we can see from Earth. One of them is Triton, in the picture at top right. The family of moons surrounding Neptune is unusual because Triton, the largest, is over 1,600 miles in diameter and the rest of them are tiny, some as small as twenty miles in diameter.  Almost all of Neptune's eight moons are too small to see from Earth, so what little we do know about them came from the Voyager space mission. Voyager took this picture of Proteus (center right) as it flew by Neptune on its way out of the solar system.   Triton was the last solid object Voyager would see before it left our solar system. Saving the one of its best discoveries for
      last, the spacecraft sent back pictures of nitrogen "geysers" erupting on Triton's surface. When you click on the image at bottom right, you will be able to see the plumes in the larger picture.

 How Did It Get Its Name?
      Neptune is named for the Roman god of the sea, but even more interesting is the fact that astronomers were actually looking for it. After William Herschel discovered Uranus, astronomers noticed that its orbit, or path, didn't seem to obey the laws of physics. Something was making Uranus move in unexpected ways. Astronomers decided that there must be another planet making Uranus move and then calculated where the new planet might be. Astronomers Galle and d'Arrest discovered Neptune on September 23, 1846. 

 What Is It Made Of?
      Neptune has a small central core, or ball, made of up melted rock. Above the rocky center, the planet is covered by extremely cold water, which eventually changes into the top layer of hydrogen and helium, with a little methane mixed in. The methane is what gives Neptune its color.

 What's It Like On The Surface?
      Since Neptune is a gas planet, it does not have a solid surface like we do here on Earth. In spite of this, Neptune has some of the most unusual "weather" in the solar system. The winds on Neptune can blow as fast as twelve hundred miles per hour at the  planet's equator! The clouds that you see in some of the pictures above are actually frozen water.