Neptune
Planet index

Neptune is the 8th Planet in the Solar System and is the last of the gas giants moving outward from the Sun. The atmosphere is very similar to Uranus is composed of hydrogen, helium and methane. The blue green colour comes from the 3% methane present.

Neptune has a storm visible on its surface dubbed the Great Dark Spot which was first viewed by the Voyager 2 spacecraft in 1989.

Neptune does have a ring system but is by far the faintest of all the gas giants rings. It is thought that in maybe 50 million years, Neptunes largest Satellite, Triton will break up and form a far more substantial ring system. The reason for this is because Triton`s orbit is in a decline, bringing it closer and closer to Neptune. This will cause great gravitational forces that will eventually shatter the satellite.

Triton has a peculiar feature not present with any other major body in the Solar System. It is in a retrograd orbit, which means it is orbiting Neptune the oposite way to the other Satellites. Almost all of the planetary orbits are in an anti clockwise motion. Triton`s orbit is clockwise.


Courtesy of NASA/JPL/Caltech

Planetary Information
Maximum Distance from the Sun4537MKms
Minimum Distance from the Sun4456MKms
Diameter50538 km
Mass17.2
Sidereal period165y
Rotation period16h 7m
Velocity23.9 km/s
Gravity1.2
Mean Temperature-220 C
Number of Moons8
Escape Velocity76700 km/h