Neptune is today , July 12, a Neptunian year, that is, 164.79 Earth years , since its discovery on September 24, 1846.
It is the outermost planet of the gas giants , with an equatorial diameter of 49,500 kilometers, and was named in honor of the Roman god of the sea, due to its blue-green color. If Neptune were empty, it would contain about 60 Earths. Its weight exceeds that of 17 planets like ours and it has eight moons, the largest of which is Triton, formed by ice and orbiting the planet in the opposite direction to the other moons (retrograde motion). A Neptune day lasts 16 hours and 6.7 minutes.
Neptune was the first planet discovered by deduction, that is, from the mathematical data obtained by Leverrier from the orbital perturbations of Uranus. The first to observe it was Johann Gottfried Galle, in 1846. The Voyager 2 probe flew over it in August 1989, and confirmed the presence of several thin rings around the planet.
Neptune's inner two-thirds are made up of a mixture of molten rock, water, ammonia, and liquid methane . The outer third is a mixture of hot gases composed mainly of hydrogen and methane. Methane gives Neptune's clouds their characteristic blue color.
On this planet the strongest winds measured anywhere else in the solar system. Near the Great Dark Spot, a hurricane storm, winds are estimated to blow at nearly 2,000 kilometers per hour.
