Dwarf planets are celestial bodies that orbit the sun but are not large enough to be considered a full-fledged planet. The three most well-known dwarf planets are PLUTO, Eris, and CERES. PLUTO is the most famous of the three, having been classified as a planet until 2006 when it was reclassified as a dwarf planet. Eris is the most distant known dwarf planet, located beyond the orbit of Neptune. Finally, CERES is the largest and closest dwarf planet to the sun, located in the asteroid belt between Mars and Jupiter.