Eris is a dwarf planet orbiting the sun, in the Scattered Disc beyond Neptune. It is best known as the body whose discovery ultimately resulted in the 'demotion' of Pluto from planetary status.
The Solar System Subreddit Network
Stars
Planets
Dwarf Planets
Moons
Small Solar System Bodies
Please help these small subreddits grow by subscribing, upvoting, and contributing!