A dwarf planet is a type of celestial object that orbits the sun. Dwarf planets are not true planets because they are not massive enough to clear other debris from their orbits. In 2006, the International Astronomical Union officially recognized a number of dwarf planets, and there are nine dwarf planets in our solar system.  The names of the nine dwarf planets are: Ceres, Pluto, Haumea, Makemake, Eris, Sedna, Quaoar, Orcus and 2007 OR10.