Neptune

Neptune is the eighth and farthest planet from the Sun in the Solar System. It rotates faster than Earth so a day in Netune lasts less (16 hrs.) than a day on Earth (24 hrs.). It´s the fourth-largest planet by diameter and the third-largest by mass. Among the gaseogus planets in the Solar System, Neptune is the most dense. Also, is 17 times the mass of Earth and slightly more massive than Uranus. Neptune orbits the Sun at an average distance of 2793.9 millions of miles. It has a size of 30,800 miles (diameter). It doesn´t have any rings. Unlike Mercury, Neptune has 13 moons. Scientists learned that neptune has 3 arcs and 6 moons because of pictures taken by the Voyager 2. With a revolution of 164.79 years, Neptune is the planet that takes mote time to encircle the Sun. Neptune has the coldest temperature of all the planets because its distance from the sun is the largest. Its temperature is of -330 °F meanwhile Mercury has a temperature of -350 °F on its dark side. Venus has an atmosphere composed of carbon dioxide, by the other side, Neptune is composed of hydrogen, helium and methane. Unlike Earth, Neptune has no oxygen. It was the first planet found by mathematical prediction rather than by empirical observation. Neptune was observed on 23 September 1846 by Johann Galle, and its largest moon, Triton, was discovered shortly after. The rest of the mooons were located until the 20th. Century. Neptune was visited by Voyager 2, when it flew by the planet on 25 August 1989.

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