Pluto is a dwarf planet in the Kuiper belt discovered in 1930. Pluto, named after the Roman god of the underworld, was downgraded from planet to dwarf planet by the International Astronomical Union (IAU) in 2006.
Pluto is a dwarf planet found in the Kuiper belt discovered in 1930 by Clyde Tombaugh. There were many suggestions for the name of the new planet. It was ultimately named Pluto after a suggestion by an 11 year-old girl named Venetia Burnley. She named the dwarf planet after the Roman god of the underworld. Pluto is the largest dwarf planet in the solar system and the second most massive after Eris. When it was first discovered, Pluto was classified as a planet and remained as such until 2006. In 2006 the International Astronomical Union created an official definition for a planet. As a result, Pluto was reclassified as a dwarf planet. Pluto has five known moons, the largest known as Charon after the ferryman on the River Styx in mythology. Charon is roughly half the size of the Pluto.
Pluto was first visited by a spacecraft when New Horizons spacecraft flew past the dwarf planet. The mission which was launched in 2006 made a flyby in 2015. During the flyby, the spacecraft sent data back to Earth about Pluto’s geology, as well as photos of the surface of Pluto and its moon, Charon.
Pluto’s rotation is also unlike most of the planets in our solar system. Like Uranus, it rotates on its side. Pluto’s orbit is also very different from the other planets’ orbits; it doesn’t lie in the same orbital plane with the eight planets of our solar system. Pluto's orbit is also moderately eccentric, meaning that for a small part of its orbital path, it is closer to the Sun than Neptune is.
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