Neptune is named after
the Roman god of the sea. Seen through the telescope this planet appears
as a tiny pale bluish dot. What we learned of this world was from Voyager
2 in 1989. This spacecraft passed within 4400 km of Neptune and returned
breathtaking pictures of the planet, its rings and its moons..
Neptune truly is out in the deep of the solar system, being over 30 times farther from the Sun than Earth. It is so far out that Neptune takes 165 years to make one trip around the Sun! Though its year is so long, Neptune spins fast, a day lasting 16 hours 3 minutes.
Neptune has a few things in common with its closest neighbor Uranus. Neptune is only 4 percent smaller with a diameter of 49,5000 km (about 4 times the size of Earth.) Both planets have a bluish color and have rings, but Neptune's equator is only tilted 28 degrees to its orbit. In other ways, Neptune is a very different world from Uranus.