Neptune is the eighth planet from the sun, the fourth largest, and a gas planet. It is named after the Roman god of the sea. Neptune is four times the size of Earth, and its day lasts a little more than 16 hours. Its year is about 165 Earth years. Neptune's orbit is a perfect circle. Neptune was the last stop on spacecraft Voyager's epic trip through the solar system. From earth, Neptune appears to be an interesting blue world. Even so, this mysterious planet had many surprises for us. The first big surprise was that the blue world has winds in its outer layer that move at hundreds of miles per hour. In fact, the winds on Neptune are the fastest in our solar system. Also, the planet has different-colored bands that are nearly as pronounced as those on Jupiter.