How Are Planets and Dwarf Planets Similar?

As of 2015, scientists define dwarf planets as bodies that are similar to planets in that they orbit a star, are large enough to form a round shape and are not moons. However, dwarf planets do not have sufficient gravity to push away other bodies that might intersect their orbits.

In 2006, the International Astronomical Union reclassified Pluto as a dwarf planet because similar objects were discovered deeper in the Kuiper Belt that also exhibited orbits that did not clear out their local neighborhoods. The first five recognized dwarf planets, in order of size, are Eris, Pluto, Haumea, Makemake and Ceres.