NASA upgrades 'Snow White' to our system's third-largest dwarf planet
 

Meet 2007 OR10: "the largest unnamed world in our solar system," according to NASA. At 955 miles in diameter, the dwarf planet is about two-thirds the size of Pluto, and is believed to have both water ice and methane on its surface.

http://www.engadget.com/2016/05/13/n...largest-dwarf/