Observation data Epoch J2000.0 Equinox J2000.0 |
|
---|---|
Constellation | Grus |
Right ascension | 21h 33m 33.975s |
Declination | −49° 00′ 32.42″ |
Apparent magnitude (V) | 8.66 |
Characteristics | |
Spectral type | M2V |
B−V color index | 1.52 |
Astrometry | |
Radial velocity (Rv) | 18.0 km/s |
Proper motion (μ) |
RA: −46.05 ± 0.95 mas/yr Dec.: −817.63 ± 0.59 mas/yr |
Parallax (π) | 201.87 ± 1.01mas |
Distance | 16.16 ± 0.08 ly (4.95 ± 0.02 pc) |
Absolute magnitude (MV) | 10.19 |
Details | |
Mass | 0.45 ± 0.05 M☉ |
Radius | 0.48 R☉ |
Luminosity (bolometric) | 0.035 L☉ |
Luminosity (visual, LV) | 0.007 L☉ |
Surface gravity (log g) | 4.7 cgs |
Temperature | 3,620 K |
Metallicity | −0.31 ± 0.2 |
Rotation | ±9.3 d 45.7 |
Age | 9.24 Gyr |
Other designations | |
Database references | |
SIMBAD | The star |
planet c | |
planet b | |
Exoplanet Archive | data |
Extrasolar Planets Encyclopaedia |
data |
Data sources: | |
Hipparcos Catalogue, HD |
Gliese 832 (Gl 832 or GJ 832) is a red dwarf of spectral type M2V in the southern constellation Grus. The apparent visual magnitude of 8.66 means that it is too faint to be seen with the naked eye. It is located relatively close to the Sun, at a distance of 16.1 light years and has a high proper motion of 818.93 mas per year. Gliese 832 has just under half the mass and radius of the Sun. Its estimated rotation period is a relatively leisurely 46 days. The star is roughly 9.5 billion years old.
In 2014, Gliese 832 was announced to be hosting the closest potentially habitable Earth-mass-range exoplanet to the Solar System. This star achieved perihelion some 52,920 years ago when it came within an estimated 15.71 ly (4.817 pc) of the Sun.
Gliese 832 hosts two known planets.
In September 2008, it was announced that a Jupiter-like planet, now designated as Gliese 832 b, had been detected in a long-period, near-circular orbit around this star (false alarm probability thus far: a negligible 0.05%). It would induce an astrometric perturbation on its star of at least 0.95 milliarcseconds and is thus a good candidate for being detected by astrometric observations. Despite its relatively large angular distance, direct imaging is problematic due to the star–planet contrast.
In 2014, a second planet was discovered by astronomers at the University of New South Wales. This one is believed to be of super-Earth mass and has since been given the scientific name Gliese 832 c. It was announced to orbit in the optimistic habitable zone but outside the conservative habitable zone of its parent star.