Fourth largest planet in the Solar System.
(nearly four times the size of Earth.)
- eighth planet out from the Sun – so far away from the Sun that its orbit lasts 165 years.
- still not yet completed one orbits since it was discovered in 1846.
- similar to Uranus – Neptune is shrouded in blue methane clouds at -210ºC in a deep atmosphere made of hydrogen and helium gas.
- nothing similar to Uranus, which is perfectly blue, Neptune has some white clouds, created by heat inside the planet.
- Neptune suffers the most violent weather in the Solar System – blowing at up to 1,250 mph.
- The Great Dark Spot was a giant storm seen by Voyager 2 in 1989, but now it has disappeared since.
- Neptune has some moons; Triton, Nereid, Proteus, Thalassa, Psamathe, Laomedeia,Larissa, Despina, Galatea, Halimede, Naiad, Sao, Neso.
- Neptune spins on its axis very rapidly;
Its equatorial clouds take 18 hours to make one rotation. This is because Neptune is not solid body.
- Neptune has 14 moons;
The most interesting moon is Triton, a frozen world that is spewing nitrogen ice and dust particles out from below its surface. It was likely captured by the gravitational pull of Neptune – probably the coldest world in the solar system.
Neptune’s largest moon and is the only large moon in the solar system to orbit in the opposite direction to its planet’s rotation.
Back to Solar System page.