Dwarf Planet Eris

An artist's view of Eris

In July, 2005 astronomers announced the discovery of a new body -- the largest object found in orbit around the Sun since the discovery of Neptune and its moon Triton in 1846. It is larger than Pluto, discovered in 1930. Like Pluto, it is a dwarf planet found in the Kuiper belt, a swarm of icy bodies beyond Neptune in orbit around the sun.

In September 2006 it was officially named Eris. It was previously known as 2003 UB313 and by its nickname, "Xena".

The discovery was made using the Palomar Observatory's 48-inch Samuel Oschin Telescope as a part of ongoing survey of the outer solar system.

To find objects, they take three pictures of a small region of the night sky over three hours and look for something that moves. The many billions of stars and galaxies visible in the sky appear stationary, while satellites, planets, asteroids, and comets appear to move.

At left is a diagram showing the relative sizes of Earth, Pluto, Eris and other distant solar system objects.

 

 

 

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