| Average Distance From Sun: | 4500 Million KM |
| Diameter: | 49,000 KM |
| Mass: | 17.25 x Earth Standard |
| Gravity: | 1.05 x Earth Standard |
| Atmosphere: | Very Cold Gases |
| Moon: | 8 |
| Neptune Year: | 165 Earth Years |
| Neptune Day: | 19 Earth hours |
Neptune is the eighth planet in average distance from the Sun.
It has three narrow orbital rings enclosed in a disc of dust that may reach down to the Neptunian cloud tops. Neptune has two named moons (Triton and Nereid), and six more discovered by the Voyager 2 probe in 1989, of which 1989 N1 (diameter 418 km/260 mi) is larger than Nereid.
Neptune was located 1846 by Galle and D'Arrest after calculations by Adams and Leverrier had predicted its existence on the basis that another body must be disturbing the orbit of Uranus. The cameras of Voyager 2, which passed Neptune in Aug 1989, revealed a wide variety of cloud features. Notable among these were bright polar collars and broad bands in different shades of blue girdling Neptune's southern hemisphere.
The blue colouring results from the absorption of red light by the methane in the atmosphere. Another cloud feature is an Earth-sized oval storm cloud, which has been named the Great Dark Spot, and has been likened to the Great Red Spot on Jupiter.
Above and around it, cirrus-type clouds of frozen methane are forming and taking shape, with winds of up to 2,400 kph. Neptune is believed to have a central rocky core covered by a layer of ice.