Astronomy Closer Look: Neptune

Discussion in 'Astronomy' started by JcMinJapan, Sep 12, 2004.

  1. JcMinJapan

    JcMinJapan Premium Member

    First discovered in 1846 by Johann Galle

    Neptune is the eighth planet from Sun at at distance of 4,504,000,000 km or 30.06 AU in distance.

    One day on Neptune is equal to 0.75 Earth days while it`s year is equal to 164.83 Earth years

    There are 11 satellites (moons), plus some rings. Triton (the largest), Naiad, Thalassa, Despina, Galatea, Larissa, Proteus & Nereid. On the 13 January, 2003, the discovery of 3 further moons, 30 - 40km in diameter, was announced

    It is also the 4th largest planet with a diameter of 49,528 km and a mass of 1.0247e26 kg

    The atmosphere is composed hydrogen, helium, methane, with traces of ammonia and water.

    Cool Facts:

    Voyager 2 is the only spacecraft to make contact and that was in 1989.

    The blue color of the planet is due to the absorption of red light by methane in the atmosphere.

    Neptune has the stronger winds than any other planet in the Solar System. Winds on will blow at 2,000 km/hour (1,200 miles/hour).

    It is named after the Roman god of the sea. British astronomer, the Astronomer Royal, John Flamsteed observed it as early as 1690, but he thought it was a star.

    It is as large as 60 Earths.

    Its existence was first predicted by two mathematicians working independently, Adams and Le Verrier because the orbit of Uranus was not as astronomers expected, therefore, according to Newton's laws of motion, there must have been another body in the solar system disturbing the orbit of Uranus. Thus Neptune was the first planet to be found by mathematical prediction.

    Triton orbits Neptune opposite to the direction of the planet’s rotation, and is gradually getting closer. It will eventually collide with the planet in 10 - 100 million years time, forming rings around Neptune that will rival or exceed Saturn’s ring system.

    For very detailed information and great photos of Uranus visit NASA