Gliese 12 (GJ 12) is a red dwarf star located 39.7 light-years (12.2 parsecs) away in the constellation Pisces. It has about 24% the mass and 26% the radius of the Sun, and a temperature of about 3,296 K (3,023 °C; 5,473 °F). It is an inactive star and hosts one known exoplanet.[5]
| |
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Pisces[1] |
Right ascension | 00h15m 49.24231s[2] |
Declination | +13° 33′ 22.3163″[2] |
Apparent magnitude (V) | 12.6[3] |
Characteristics | |
Evolutionary stage | main sequence |
Spectral type | M4V[4] |
Apparent magnitude (V) | 12.600±0.04[3] |
Apparent magnitude (R) | 12.296±0.08[3] |
Apparent magnitude (G) | 11.399±0.003[2] |
Apparent magnitude (J) | 8.619±0.020[3] |
Apparent magnitude (H) | 8.068±0.026[3] |
Apparent magnitude (K) | 7.807±0.020[3] |
Astrometry | |
Radial velocity (Rv) | 51.04±0.26[2] km/s |
Proper motion (μ) | RA: 618.065 mas/yr[2] Dec.: 329.446 mas/yr[2] |
Parallax (π) | 82.1938 ± 0.0326 mas[2] |
Distance | 39.68 ± 0.02 ly (12.166 ± 0.005 pc) |
Details[5] | |
Mass | 0.2414±0.0060 M☉ |
Radius | 0.2617+0.0058 −0.0070 R☉ |
Luminosity (bolometric) | 0.00728±0.00015 L☉ |
Surface gravity (log g) | 5.21±0.07 cgs |
Temperature | 3,296+48 −36 K |
Metallicity [Fe/H] | −0.32±0.06 dex |
Rotation | 85 days |
Rotational velocity (v sin i) | <2 km/s |
Age | 7.0+2.8 −2.2[6] Gyr |
Other designations | |
GJ 12, G 32-5, L 1154-29, LHS 1050, LP 464-42, LTT 10083, NLTT 786, PLX 42, TOI-6251, TIC 52005579, 2MASS J00154919+1333218[3] | |
Database references | |
SIMBAD | data |
The transiting exoplanet Gliese 12 b was discovered by TESS, and two independent studies confirming it as a planet were published in May 2024.[5][6] Gliese 12 b is similar in size to Earth and Venus, and completes an orbit around its star every 12.8 days. Its mass is poorly constrained but is known to be less than 4 times that of Earth.[5]
Along with the planets of TRAPPIST-1, Gliese 12 b is one of the nearest known relatively temperate transiting exoplanets, and so is a promising target for the James Webb Space Telescope to determine whether it has retained an atmosphere.[7] Gliese 12 b orbits slightly closer than the inner edge of its star's habitable zone, with an insolation between those of Earth and Venus.[6] Its equilibrium temperature, assuming zero albedo, is 315 K (42 °C; 107 °F); if it has an atmosphere, the surface temperature would be greater than this.[5]
Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | <3.87 M🜨 | 0.0668±0.0024 | 12.761408±0.000050 | <0.50 | 89.194+0.059 −0.052° |
0.958+0.046 −0.048 R🜨 |