Double planet arguing that Jupiter is a double star is "not" analogous to arguing Pluto-Charon is a double dwarf planet. The problem is that Jupiter is not even a star, or even a brown dwarf, and due to its low mass it is unable to achieve any form of fusion. Isaac Asimov suggested a distinction between planet–moon and double-planet structures based in part on what he called a "tug-of-war" value, which does not consider their relative sizes. This quantity is simply the ratio of the force exerted on the smaller body by the larger (primary) body to the force exerted on the
Eris (dwarf planet) object was classified as a dwarf planet, because there is already an asteroid with that name, 399 Persephone. With the dispute resolved, the discovery team proposed "Eris" on September 6, 2006. On September 13, 2006 this name was accepted as the official name by the IAU. Brown decided that, because the object had been considered a planet for so long, it deserved a name from Greek or Roman mythology, like the other planets. The asteroids had taken the vast majority of Graeco-Roman names. "Eris", whom Brown described as his favorite goddess, had fortunately escaped inclusion. The name in part reflects