Eris: The Distant Rival to Pluto

Eris is one of the most massive known dwarf planets, discovered in 2005.
Its discovery sparked the debate that led to Pluto’s reclassification.
Eris is about the same size as Pluto but slightly more massive.
It orbits the Sun in the distant scattered disk, far beyond Neptune.
A single orbit around the Sun takes Eris 557 Earth years.
Its surface is covered with frozen methane, making it bright and reflective.
Eris has one known moon, Dysnomia, discovered shortly after Eris itself.
Dysnomia’s orbit helped scientists measure Eris’s mass precisely.
Eris is so far away that sunlight takes over nine hours to reach it.
It was nearly named “Xena” before officially becoming Eris, after the Greek goddess of strife.