The Satellite of Eris

Abstract

A Trans-Neptunian Object (TNO) larger than Pluto was discovered by Michael Brown (Caltech), Chad Trujillo (Gemini Observatory) and David Rabinowitz (Yale University) in CCD photographs taken on October 21, 2003 with the 1.2 m-Schmidt telescope at the Mount Palomar Observatory, and confirmed on January 5, 2005.The provisional designation was 2003 UB 313. Considering the (relatively new) tradition of naming TNOs after creation deities (among others), such as Quaoar and Varuna, Brown’s first idea was to name this object Lila, a Hindu description for the periodical creation of the universe as a divine “game” (the Sanskrit meaning of Lila). The name of Brown’s (then three-week-old) daughter was also Lilah. On September 10, 2005, however, a satellite of 2003 UB 313 was discovered by Brown and his team and designated S/2005 (2003 UB 313). The ratio of its albedo to that of 2003 UB 313, is 1:8. Inspired by the Centaur asteroids, which are probably extinct comets that orbit the Sun between Jupiter and Neptune, Brown then had the idea of naming 2003 UB 313 and its satellite Xena and Gabrielle, characters from the US and New Zealand TV series Xena: Warrior Princess which aired from 1995 to 2001 (Xena and Gabrielle support the people of Centaur when fighting against the evil warrior Dagnine).