This object moves — fetching its current position…
Score breakdown
· 8 badges
105 pts · Anomaly
Anomaly120 pts → Mythic
Eris, the world that demoted Pluto+24
Giant body (>500 km)+22
Dwarf planet+16
Far-flung orbit (a > 50 AU)+14
Trans-Neptunian object+12
Has a proper name+8
Has moons+5
Steeply tilted orbit (i > 40°)+4
Total score105
15 more points to reach Mythic.
Badges
⚪Dwarf planet· +16
🏔️Giant body (>500 km)· +22
🏷️Has a proper name· +8
🌙Has moons· +5
🌨️Trans-Neptunian object· +12
🛤️Far-flung orbit (a > 50 AU)· +14
📏Steeply tilted orbit (i > 40°)· +4
🍏Eris, the world that demoted Pluto· +24
✨ Trivia
Hard to believe
🥇Round under its own weight. Big enough that its own gravity has pulled it into a sphere — most of its neighbours are potato-shaped rubble.
What it actually is
🛸Its orbit family. A trans-Neptunian object from the Kuiper Belt, out where the Sun is little more than the brightest star in a very dark sky.
🔁One lap. A single orbit around the Sun takes it about 558 years.
🥏How far it roams. Its orbit swings between 37.91 and 97.65 AU from the Sun.
📐Steeply tilted. Its orbit is tipped 44° out of the flat plane the planets share — it spends most of its time well above or below them.
Sense of scale
🧱Sense of scale. In everyday terms it is about 67% as wide as our Moon.
🚶Walk around it. Walking its equator at a steady pace, eight hours a day, would take about 6 months.
🌍Against Earth. It is only 18% of Earth's width — you could pack about 164 of it inside our planet.
Properties
aphelion au
97.6506
color
#d6d0c4
diameter km
2326
eccentricity
0.4407
inclination
44.04
name
Eris
named
yes
num moons
1
orbit class
TNO
orbital period days
203830
perihelion au
37.9094
radius km
1163
semi major au
67.78
About Eris
Eris is an anomaly dwarf planet. It completes an orbit every 203,830 days and swings within 37.909 AU of the Sun at perihelion.
A trans-Neptunian object from the Kuiper Belt, out where the Sun is little more than the brightest star in a very dark sky.
How to see it
Like any astronomical target, Eris is best seen from a dark site away from city lights, and when it is above the horizon depends on your latitude and the time of year. Because it moves against the background stars, the live position panel on this page tracks where it is right now. The visibility panel above works out tonight's viewing window for your saved location.
Why Eris is an anomaly dwarf planet
Eris scores 105 points on Spacedle's rarity scale, which places it in the anomaly tier. Another 15 points would lift it into a rarer tier.
That score comes from 8 science badges — Dwarf planet, Giant body (>500 km), Has a proper name, Has moons, Trans-Neptunian object, Far-flung orbit (a > 50 AU), Steeply tilted orbit (i > 40°) and Eris, the world that demoted Pluto — each earned for a real, measurable property of the object. Rarity on Spacedle is never random: the more remarkable an object's astrophysics, the more badges it collects, the higher it scores, and the rarer it ranks.
📷 Real photo