They are in direct orbit around the sun, they have achieved hydrostatic equilibrium (are approximately spherical), but they have not managed to clear their area of other objects (the eight major anets have).
Dwarf planets are not a special type of planet. A small planet is later classified a dwarf planet. The only characteristic that makes it a dwarf planet is the size. Your question should be why are some planets small?
Pluto the dwarf planet is an example of of a dwarf planet.
The International Astronomical Union (IAU) agreed that Pluto should be classified as a dwarf planet on August 24, 2006, during their General Assembly in Prague. This decision was based on new definitions of what constitutes a planet, which led to Pluto being reclassified from a full-fledged planet to a dwarf planet.
Mercury is not a dwarf planet. It is a planet.
dwarf is a dwarf planet because it is to small to be in the solar system.,
The dwarf planet Pluto.The dwarf planet Pluto.The dwarf planet Pluto.The dwarf planet Pluto.
Hiʻiaka is the larger, outer moon of the dwarf planet Haumea.It is NOT a dwarf planet.
Ceres is a dwarf planet. There is no such thing as a gas dwarf planet - Yet!
Quaoar is an official dwarf planet.
Its still a dwarf planet
Pluto is referred to as dwarf planet.
That planet, a dwarf, is called Pluto.