Key facts
- Scale fact
- 2,326 kmmean diameter
- Estimated age
- ~4.5 billion years
- Composition
- Rock and ice
Eris
2,326 kmmean diameter
Visual creditscaleofspace.org / CC BY-NC 4.0
Details
Eris is a distant dwarf planet in the scattered disk beyond Neptune. Its discovery helped trigger the 2006 planet-definition debate, and its tiny moon Dysnomia lets astronomers measure its mass.
Eris is close to Pluto in diameter but more massive, a comparison made possible by tracking its moon Dysnomia. Its 2005 announcement sharpened the question of whether similarly sized trans-Neptunian objects should all count as planets. The resulting 2006 IAU definition placed Eris, Pluto and Ceres in the dwarf-planet category.
Links
- Preset views
- Wikipedia
- Eris on Wikipedia
- Universe journey
- Heliosphere
Size neighbors
Objects near Eris on the scale
Sources
References for Eris
Measurements and descriptive context are compiled by the Scale of Space team from the references below. If you find an error, please let us know.
- Eris — Wikipedia
- Visual: scaleofspace.org / CC BY-NC 4.0
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About
Scale of Space is a scroll-based journey through the universe, placing objects on a single logarithmic scale so you can compare size across an unbroken range.
Guides explain selected parts of that range, while focused views filter the objects by subject.