Pluto

Pluto is a dwarf planet located in the outer reaches of the Solar System, beyond Neptune, in an area called the Kuiper Belt. It is about two-thirds the size of Earth's Moon and has a rocky, icy surface. Pluto has a thin atmosphere that can change with its distance from the Sun and a complex surface with mountains, plains, and ice features. It was classified as a planet until 2006, when the International Astronomical Union redefined the term "planet," and Pluto was reclassified as a dwarf planet due to its size and inability to clear its orbit.