Eris, officially (136199) Eris, is a dwarf planet of the Solar System. It is the most massive of the known dwarf planets, the second largest and the largest known body in the Solar System that has not been visited by a space probe. It has a diameter of 2,326 ± 12 km and a mass 27% greater than that of Pluto. Instead, it only represents 0.27% of the Earth's mass. It was discovered in January 2005 by Mike Brown's team. It is a transneptunian object, a member of a population of highly eccentric objects known as Scattered Disc, and has a satellite called Dysnomia. These objects are believed to have been carried into a farther orbit than usual by gravitational interactions with Neptune in the early stages of the formation of the Solar System. In February 2016, its distance to Sol was 96.3 AU, about three times that of Pluto. With the exception of a few comets, Eris and Dysnomia were by then the most distant known natural objects in the Solar System.
