Dwarf planet a draft resolution for the IAU definition of planet, both Pluto and Charon would have been considered dwarf planets in a binary system, given that they both satisfied the mass and shape requirements for dwarf planets and revolved around a common center of mass located between the two bodies (rather than within one of the bodies). The IAU currently states that Charon is not considered to be a dwarf planet and is just a satellite of Pluto, although the idea that Charon might qualify to be a dwarf planet in its own right may be considered at a later date.
Dwarf planet history. On March 6, 2015, the "Dawn" spacecraft began to orbit Ceres, becoming the first spacecraft to orbit a dwarf planet. On July 14, 2015, the "New Horizons" space probe flew by Pluto and its five moons. Dawn has also explored the former dwarf planet Vesta. Phoebe has been explored by Cassini (most recently) and Voyager 2, which also explored Triton. These three are thought to be former dwarf planets and therefore their exploration helps in the study of the evolution of dwarf planets. In the immediate aftermath of the IAU definition of dwarf planet, some scientists expressed their disagreement