Eris: The Forgotten Tenth Planet That Could Redefine Our Solar System
Artist’s concept of Eris and its moon Dysnomia in the distant Kuiper Belt region beyond Neptune. Introduction We grew up learning there were nine planets. Then, in 2006, Pluto was erased from the list, leaving only eight. But the discovery of Eris — a frozen world orbiting far beyond Neptune — reignited one of astronomy’s…