Eris is the ninth-most massive known object orbiting the Sun and the sixteenth-most massive overall in the Solar System (counting moons). It is also the largest known object in the Solar System that has not been visited by a spacecraft.

In Greek mythology, Eris (Ancient Greek: Ἔρις, romanized: Eris, lit. 'Strife') is the goddess and personification of strife and discord, particularly in war, and in the Iliad (where she is the "sister" of Ares the god of war).

2025年3月12日 · Eris takes 557 Earth years to make one trip around the Sun. The plane of Eris' orbit is well out of the plane of the solar system's planets and extends far beyond the Kuiper Belt, a zone of icy debris beyond the orbit of Neptune.

2019年10月8日 · Eris is the most distant dwarf planet, located beyond the orbit of Neptune. It was discovered in 2005 and was originally classified as a planet. It is the second-largest dwarf planet discovered and it led to both it and Pluto’s demotion from planets to dwarf planets.

Eris is one of the largest known dwarf planets in our solar system. It's about the same size as Pluto but is three times farther from the Sun. At first, Eris appeared to be larger than Pluto.

2025年2月28日 · Eris, in Greco-Roman mythology, the personification of strife. She was called the daughter of Nyx (Night) by Hesiod, but she was sister and companion of Ares (the Roman Mars) in Homer’s version. Eris is best known for her part in starting the Trojan War.

2025年1月30日 · Eris, large, distant body of the solar system, revolving around the Sun well beyond the orbits of Neptune and Pluto in the Kuiper belt. It was discovered in 2005 in images taken two years earlier at Palomar Observatory in California, U.S.