Epsilon Eridani

Epsilon Eridani

system

Epsilon Eridani (Ran) is a young orange dwarf (K2V) 10.5 light-years away in Eridanus, one of the closest planetary systems to the Sun. At only ~200–850 million years old it is still ringed by a dusty debris disk — a close analogue of our own Kuiper Belt — and hosts a confirmed gas giant, Epsilon Eridani b (AEgir). It offers a snapshot of what the young Solar System may have looked like.

Open in 3D viewSee Epsilon Eridani in the live, interactive 3D map

Key facts

Type
Young K-dwarf + disk
Distance
10.5 light-years
Confirmed planets
1
Debris disk
Yes

Science

Classification

Type
Young single-star system (K2V)
Central star
Epsilon Eridani / Ran — orange dwarf (~5084 K, 0.82 M☉)

Contents

Confirmed planets
1 · Epsilon Eridani b (AEgir), a gas giant at 3.5 AU
Debris disk
Yes — a dust ring peaking ~65–70 AU · a Kuiper-belt analogue, detected 1998

Distance & age

Distance
10.5 light-years · one of the closest planetary systems
Age
~200–850 million years · estimated — far younger than the Sun

How we know

Note
Epsilon Eridani b is confirmed (NASA Exoplanet Archive, checked 2026-07-04); its mass is a true dynamical mass from astrometry, but it has never transited or been imaged, so its radius and appearance are model-based (the map shows a flat spectral-colour gas giant, not a fabricated surface). The debris disk is real and detected; it is rendered as a faint dust ring at its true ~65 AU scale. On the map the system sits at a usable distance; the real gap is 10.5 light-years.

Discovery & history

Method
Naked-eye star
Name
Its IAU proper name Ran (2015) is the Norse sea goddess; its planet is AEgir, her husband. 'Epsilon Eridani' is the Bayer designation for a star in Eridanus, the River.

Known since antiquity in Eridanus, the River, Epsilon Eridani was — like Tau Ceti — a target of Frank Drake's 1960 Project Ozma. Its debris disk was found in 1998 and its gas giant in 2000, making it one of the most-studied young planetary systems beyond our own.

Images

Artist's concept of the Epsilon Eridani system — a gas giant, dusty belts and comets around the young star; not a photograph
NASA / JPL-Caltech (public domain) · Wikimedia Commons
The REAL debris ring, imaged by ALMA at 1.3 mm — the clumpy dust belt lies ~70 AU from the star (the bright point at centre)
ALMA (ESO/NAOJ/NRAO) / Mark Booth (CC BY-SA 4.0) · Wikimedia Commons
Where to find it — Epsilon Eridani (Ran) in Eridanus, the River (IAU chart)
IAU / Sky & Telescope, R. Sinnott & R. Fienberg (CC BY 3.0) · Wikimedia Commons

Images from open archives · credit shown per image