Eris
Eris
Dwarf planet · 67.86 AU from the Sun
Eris facts
- Type
- Dwarf planet
- Distance from the Sun
- 67.86 AU (1.02 × 10¹⁰ km)
- Orbital period (year)
- 559 Earth years
- Diameter
- 2,326 km
- Mass
- 1.64 × 10²² kg
- Moons
- 1
- Rotation period (day)
- 15.8 Earth days
- Mean temperature
- -231 °C
- Discovered
- 2005, by Michael Brown's team
Orbit
About Eris
Eris is a distant, massive dwarf planet in the scattered disc beyond the Kuiper Belt. Its discovery, as an object more massive than Pluto, triggered the 2006 debate that redefined what counts as a planet. Its highly tilted, stretched orbit carries it out to about 98 AU at its most distant, more than twice Pluto's average distance from the Sun.
- Named after the Greek goddess of strife and discord
- Discovered: 2005, by Michael Brown's team
Eris: frequently asked questions
- What is Eris?
- Eris is a dwarf planet in our Solar System, orbiting the Sun at an average distance of 67.86 AU (1.02 × 10¹⁰ km). Eris is a distant, massive dwarf planet in the scattered disc beyond the Kuiper Belt.
- How far is Eris from the Sun?
- Eris orbits the Sun at an average distance of 67.86 AU, about 1.02 × 10¹⁰ km. One AU is the Earth-Sun distance, so Eris is roughly 67.9 times Earth's distance from the Sun.
- How long is a year on Eris?
- Eris takes 559 Earth years to complete one orbit of the Sun, which is one Eris year. By Kepler's third law, bodies farther from the Sun take longer to go around.
- How many moons does Eris have?
- Eris has 1 known moon.
- How big is Eris?
- Eris has a diameter of about 2,326 km and a mass of roughly 1.64 × 10²² kg.
- Why is Eris a dwarf planet and not a planet?
- Eris orbits the Sun and is round, but it has not cleared its orbital neighbourhood of other objects, the third rule the International Astronomical Union set in 2006. Bodies that meet the first two rules but not the third are called dwarf planets.
See Eris in motion
Data from NASA/JPL and NSSDCA. Source.