Eris (dwarf planet)

Eris was discovered in January 2005 by a Palomar Observatory-based team led by Mike Brown. In September 2006 it was named after the Greco-Roman goddess of strife and discord. Eris is the ninth-most massive known object directly orbiting the Sun. It is also the largest object that has not been visited by a spacecraft. Its mass is 0. 27 percent...