Eris (dwarf planet)

Most massive dwarf planet

Eris (minor-planet number 136199) is the most massive and second-largest-known dwarf planet in the Solar System. It is a trans-Neptunian object (TNO) in the scattered disk and has a high-eccentricity orbit. Eris was discovered in January 2005 by a Palomar Observatory–based team led by Mike Brown and verified later that year.

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