Gliese 876
Gliese 876 is a red dwarf about 15 light-years away from Earth in the constellation of Aquarius.[1] It is the closest star known to be a multiplanetary system. As of 2011, four extrasolar planets have been found orbiting the star.[2]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Aquarius |
| Pronunciation | /ˈɡliːzə/ |
| Right ascension | 22h 53m 16.7323s |
| Declination | −14° 15′ 49.3034″ |
| Apparent magnitude (V) | 10.15 |
| Characteristics | |
| Spectral type | M4V |
| U−B color index | 1.15[source?] |
| B−V color index | 1.59[source?] |
| V−R color index | 0.30[source?] |
| R−I color index | 1.22[source?] |
| Variable type | BY Draconis |
| Astrometry | |
| Radial velocity (Rv) | –1.519 ± 0.157 km/s |
| Proper motion (μ) | RA: 957.961±0.117 mas/yr Dec.: −673.638±0.102 mas/yr |
| Parallax (π) | 213.8669 ± 0.0758 mas |
| Distance | 15.250 ± 0.005 ly (4.676 ± 0.002 pc) |
| Absolute magnitude (MV) | 11.79[source?] |
| Details | |
| Mass | 0.37 M☉ |
| Radius | 0.3761±0.0059 R☉ |
| Luminosity | 0.0122±0.0002 L☉ |
| Surface gravity (log g) | 4.89 cgs |
| Temperature | 3129±19 K |
| Metallicity [Fe/H] | +0.19 ± 0.17 dex |
| Rotation | 96.9 days |
| Rotational velocity (v sin i) | 0.16, km/s |
| Age | 0.1–9.9 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | Gliese 876 |
| d | |
| c | |
| b | |
| e | |
| Exoplanet Archive | data |
| ARICNS | data |
| Extrasolar Planets Encyclopaedia | data |
It is the third closest known star to the Sun which has a planetary system, after Epsilon Eridani (10.5 ly) and Gliese 674 (14.8 ly).
Two of the middle planets are in the system's habitable zone. However, they are giant planets thought to be like Jupiter.
Gliese 876 Media
A visual band light curve for IL Aquarii, adapted from Hosey et al. (2015)
The orbits of the planets of Gliese 876. Note that the strong gravitational interactions between the planets causes rapid orbital precession, so this diagram is only valid at the stated epoch.
References
- ↑ Correia A.C M. et al. 2010. The HARPS search for southern extra-solar planets. XIX. Characterization and dynamics of the GJ 876 planetary system. Astronomy and Astrophysics 511: A21. [1]
- ↑ Rivera, Eugenio J. et al. 2010. The Lick-Carnegie Exoplanet Survey: a Uranus-mass fourth planet for GJ 876 in an extrasolar Laplace configuration. The Astrophysical Journal 719 (1): 890–899. [2]
