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.
  • Triton;
    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.

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