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).

5 days ago · 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.

Oct 8, 2019 · 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.

Eris is said to be the child of Zeus and Hera, the king and queen of the gods of Olympus, but in other myths, she’s the daughter of Erebus and Nyx, the king and queen of the darkest night. When she had a son, she named him “Strife” and took him along in her chariot when she and Ares went to war.

Eris is the most massive dwarf planet in the Solar System, exceeding Pluto’s mass by 28%. As such, it was a serious contender to be a tenth planet but failed to meet the criteria set out by the International Astronomical Union in 2006. Eris was named after the Greek goddess of discord.

Jan 30, 2025 · 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.

Jan 31, 2025 · Eight billion miles (14 billion kilometers) from Earth, at the solar system’s ragged edge, lies Eris — a planet-sized oddball of a world that emerged unexpectedly from the darkness 20 years ago.

Feb 28, 2025 · 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.