Epsilon Indi

Star

Epsilon Indi - a bright orange dwarf (K5V) just 11.9 light-years away in Indus, one of the nearest stars visible to the naked eye. It hosts a cold super-Jupiter (Epsilon Indi Ab) on a wide orbit, and - far out at ~1,460 AU - a pair of brown dwarfs, among the nearest known.

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

Key facts

Mass

1.55 × 10³⁰ kg

0.781 M☉

Radius

472,380 km

68% of the Sun's radius

Surface temperature

4,760 K (4487 °C)

Luminosity

9.15 × 10²⁵ W

Spectral type

K5V (orange dwarf)

Science

Physical

Mass: 1.55 × 10³⁰ kg · 0.781 M☉
Radius: 472,380 km · 68% of the Sun's radius
Density: 3,518 kg/m³ · 3.5× water
Spectral type: K5V (orange dwarf)

Rotation

Note: Rotates about once every 35 days.

Composition

By mass: An orange main-sequence star about 78% of the Sun's mass and a quarter of its light, metal-rich and moderately active.

Temperature

Surface: 4,760 K (4487 °C)

Radiation & temperature

Luminosity: 9.15 × 10²⁵ W · 0.239 L☉
Surface temperature: 4,760 K (4487 °C)
Peak wavelength: 609 nm · orange light

Discovery & history

Method: Naked-eye star
Name: 'Epsilon Indi' is the Bayer designation for a star in Indus, the Indian. It has no widely-used proper name.

Known since antiquity as a star of the southern sky, Epsilon Indi was long prized as a Sun-like neighbour. Its brown-dwarf companions were found in 2003; a giant planet's slow radial-velocity wobble was tracked over two decades, and in 2024 JWST directly imaged the planet - one of the first images of a planet first found by the wobble it induces.

Images

Where to find it — in Indus, the Indian (IAU constellation chart). To the eye it is a single point of light; no telescope has imaged its surface. — IAU / Sky & Telescope, R. Sinnott & R. Fienberg (CC BY 3.0) · Wikimedia Commons

Images from open archives · credit shown per image