Pluto (minor-planet designation: 134340 Pluto) is the second-most massive known dwarf planet, after Eris. It is the largest object in the Kuiper belt[h][i] and possibly the largest known trans-Neptunian object. It is the tenth-most-massive known body directly orbiting the Sun. Like other Kuiper belt objects, Pluto is primarily made of rock and ice
Remember when New Horizons swept past Pluto in 2015? That was exciting! Who knew Pluto had a heart? Now scientists are proposing a new Pluto orbiter mission. It would gather details on Pluto's heart and the rest of its youthful surface, its hazy bluish nitrogen atmosphere, and its system of 5 known moons.
In 1930, Venetia Burney suggested a newly discovered planet be named Pluto, after the Roman god of the underworld. Her grandfather, a retired Oxford librarian, passed on the name to an astronomer friend.
The Dwarf Planet Haumea resides in the Kuiper belt and is roughly the same size as Pluto. Haumea is one of the fastest rotating large objects in our solar system. Its fast spin distorts Haumea's shape, making this dwarf planet look like a football.