Luyten's Star

Star

Luyten's Star - a red dwarf 12.4 light-years away in Canis Minor, close in the sky to brilliant Procyon. It hosts two confirmed planets, one of them temperate - and in 2017 it was the target of a deliberate radio message to the stars.

Open in 3D viewSee Luyten's Star in the live, interactive 3D map

Key facts

Mass

5.77 × 10²⁹ kg

0.29 M☉

Radius

203,840 km

29% of the Sun's radius

Surface temperature

3,382 K (3,109 °C)

Luminosity

3.37 × 10²⁴ W

Spectral type

M3.5V (red dwarf)

Science

Physical

Mass: 5.77 × 10²⁹ kg · 0.29 M☉
Radius: 203,840 km · 29% of the Sun's radius
Density: 16,258 kg/m³ · 16× water; Computed from mass and radius
Spectral type: M3.5V (red dwarf)

Motion through space

Proper motion: 3.74 arcseconds per year · its drift across our sky; SIMBAD — 2020yCat.1350....0G, 2018MNRAS.475.1960F
Radial velocity: +18.4 km/s · moving away from the Sun; SIMBAD — 2020yCat.1350....0G, 2018MNRAS.475.1960F
Speed across our line of sight: 67 km/s; Computed from proper motion and parallax
Speed through space, relative to the Sun: 69.5 km/s; Computed from proper motion, parallax and radial velocity

Rotation

Note: Rotates about once every 99 days.

Composition

By mass: A red dwarf about 29% of the Sun's mass and ~1% of its light; relatively quiet.

Temperature

Surface: 3,382 K (3,109 °C)

Radiation & temperature

Luminosity: 3.37 × 10²⁴ W · 0.0088 L☉
Surface temperature: 3,382 K (3,109 °C)
Peak wavelength: 857 nm · near-infrared (mostly invisible to the eye); Computed (Wien's law) from the surface temperature

Discovery & history

Discovered: 1935
By: Willem Luyten
Method: Telescope
Name: Named for the Dutch-American astronomer Willem Luyten, who catalogued its proper motion; also GJ 273.

Catalogued by Willem Luyten from its large proper motion; ESO's HARPS found its two planets in 2017. That year the METI project beamed 'A Simple Response to an Elemental Message' toward its temperate planet - due to arrive in 2030.

Images

Where to find it — in Canis Minor, the Lesser Dog (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