James Webb Space Telescope image of 136199 Eris, a trans-Neptunian object.

136199 Eris

ASTEROIDTrans-Neptunian object
[

OVERVIEW

] ASTEROID

136199 Eris is a . Its absolute magnitude () is −1.26. It orbits the Sun at a mean distance of 67.93 . It is catalogued as 136199 Eris (2003 UB313). It was discovered in 2005.

The discovery that unseated Pluto: a scattered-disk object of almost the same size but greater mass, which forced the definition of "planet" to be written down.

WHAT IT IS
Trans-Neptunian object
HOW FAR
67.93

Its average distance from the Sun, not from Earth.

HOW BRIGHT IN ITSELF (H)

How bright it would look from a fixed, standard distance — a measure of the object rather than of the view from here.

ONE ORBIT TAKES
561

One trip round the Sun.

[

IMAGES

] 2 FRAMES
  • Meli thev
    CC BY-SA 4.0
  • NASA, ESA, and M. Brown (California Institute of Technology)
    Public domain
[

OBSERVING

] FROM WHERE YOU ARE

What it takes to see 136199 Eris for yourself. Everything in this part of the page is worked out for a real horizon, a real night and the equipment you say you have.

[

CATALOG DATA

] 15 FIELDS

The raw catalogue values, as the source published them, with the error bars where one was published — sorted by what each set of figures is about rather than by the order they happened to be stored in.

WHAT IT IS MADE OF

What the object is in itself, rather than how it happens to look from here.

Rotation period
25.9

THE ORBIT

The shape of the path, where the object sits on it, and the instant those figures were true of. An orbit is a fit to observations and drifts away from the real one either side of its epoch.

Orbital period
561.3 ±1.1
Eccentricity
Inclination
43.93
Longitude of ascending node
36
Argument of perihelion
150.79
Mean anomaly
211.77
Element epoch
2461200.5000
Perihelion passage
2545407.7200
Minimum distance from Earth's orbit
37.2
Orbit class
TNO

WHEN IT WAS FOUND

Who first saw it, from where, and by what method.

Discovered by
Brown, M. E., Trujillo, C. A., Rabinowitz, D. L.
Discovered from
Palomar
Discovered on
2003-10-21
First observed
1954-09-03
[

ALSO KNOWN AS

] 3 DESIGNATIONS
  • Asteroid 136199
  • Asteroid 136199 Eris (2003 UB313)
  • Common name Eris
[

LOOK IT UP ELSEWHERE

] 1 SERVICE

Each link carries the identifier printed beside it. Nothing on this page is a measurement of our own, so a number that disagrees with one of these is worth reporting — and a service that has never catalogued this object under this name will say so plainly.

[

CITE THIS PAGE

] DR1

This page is live and its numbers move when an upstream refreshes, so the citation names the release the rows belong to rather than the day you read them. The release itself is frozen, republished as a bundle, and is what a data-availability statement should point at.

PLAIN TEXT
SpaceCatalog. 136199 Eris [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/136199-eris
BIBTEX
@misc{spacecatalog_136199-eris,
  author       = {{SpaceCatalog}},
  title        = {{136199 Eris}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/136199-eris},
  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from JPL Small-Body Database.}
}

The values above were taken from JPL Small-Body Database — Public domain (NASA/JPL). Citing this page does not replace citing that catalogue.

[

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