An artist's impression of the dwarf planet Eris, and her moon, Dysnomia. That's the Sun at upper left, some 14 billion kilometres away.
Credit: NASA
SYDNEY, 14 September 2006: The distant, icy rock, whose discovery led to Pluto being stripped of its planethood has been officially named 'Eris'.
The christening was announced yesterday by the International Astronomical Union (IAU), on the same day they gave Pluto the unremarkable moniker of 134340 Pluto, according to early reports from Associated Press.
Discovered in July last year, Eris – which is larger than Pluto - ignited a fierce debate over exactly what constitutes a planet. In the fallout, Pluto was demoted to the less prestigious rank of 'dwarf planet'. The new category of celestial body also includes Eris and the asteroid Ceres.
Appropriately, the controversial lump of rock and ice has been named after the Greek goddess of chaos and strife. The new name replaces the temporary tag chosen by its discoverers: Xena, in honour of the lead character in the cult TV series, Xena: Warrior Princess.
Michael Brown of the California Institute of Technology, who discovered the dwarf planet told Associated press he was bittersweet about the new name. While he said it was sad to see Xena go, the new name was an obvious choice, calling it "too perfect to resist."
Astronomers were initially divided over how to classify Eris (pronouced Ee-ris), which has also been known by its numerical designation, 2003 UB313. Some argued that it should be welcomed as the 10th planet in our Solar System, while others said both it and Pluto were not worthy of planethood.
"I think it's bringing things back to way they should have been all along," said Bryan Gaensler, an astronomer at the University of Sydney, and member of the Editorial Advisory Board of Cosmos. "It's really a historical accident that Pluto was ever a planet in the first place."
In Greek mythology, Eris sparked the Trojan War by starting a quarrel among the goddesses. Now the celestial Eris has rolled a wooden horse into the community of astronomers, with rebel Pluto supporters calling for the new definition to be scrapped.
In all the reshuffling and renaming, Eris' moon - which was formerly known as Gabrielle - has also received a new title. Named after Eris' daughter, the spirit of lawlessness, the moon is now officially called Dysnomia.
The dwarf planet Eris, which has a diameter about 110 kilometres wider than Pluto's, is the farthest known object in the solar system, at 14 billion kilometres from the sun. It is also the third brightest object located in the Kuiper Belt, a disc of icy debris beyond the orbit of Neptune.
