Gliese 832
From Wikipedia, the free encyclopedia
(Redirected from GJ 832)
| Observation data Epoch J2000.0 Equinox J2000.0 |
|
|---|---|
| Constellation | Grus |
| Right ascension | 21h 33m 33.9752s |
| Declination | -49° 00′ 32.422″ |
| Apparent magnitude (V) | 8.66[1] |
| Characteristics | |
| Spectral type | M1.5V |
| B−V color index | 1.52[1] |
| Astrometry | |
| Radial velocity (Rv) | 18.0 km/s |
| Proper motion (μ) | RA: -46.18[2] mas/yr Dec.: -817.96[2] mas/yr |
| Parallax (π) | 202.52 ± 1.33[2] mas |
| Distance | 16.1 ± 0.1 ly (4.94 ± 0.03 pc) |
| Details | |
| Mass | 0.45 ± 0.05[1] M☉ |
| Radius | 0.48[3] R☉ |
| Luminosity (bolometric) | 0.035[note 1] L☉ |
| Surface gravity (log g) | 4.7[1] |
| Temperature | 3,620[4] K |
| Metallicity | −0.31 ± 0.2[1] |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
| Extrasolar Planets Encyclopaedia |
data |
| Data sources: | |
| Hipparcos Catalogue, HD |
|
Gliese 832 (Gl 832 or GJ 832) is a red dwarf star (spectrum M1.5V) in the constellation Grus. It is located relatively near our Sun, at a distance of 16.1 light years. The star is about half the mass and radius of the Sun.
Contents |
[edit] Jupiter-like planet
In September 2008, it was announced that a Jupiter-like planet 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. Among currently-known exoplanets, it would have an angular distance from its star second only to Epsilon Eridani b, although direct imaging is problematic due to the star–planet contrast.[1]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity |
|---|---|---|---|---|
| b | ≥0.64 ± 0.06 MJ | 3.4 ± 0.4 | 3416 ± 131 | 0.12 ± 0.11 |
[edit] X-ray source
Gliese 832 emits X-rays.[5]
[edit] See also
[edit] Notes
- ^ From L=4πR2σTeff4, where L is the luminosity, R is the radius, Teff is the effective surface temperature and σ is the Stefan–Boltzmann constant.
[edit] References
- ^ a b c d e f Bailey, Jeremy et al. (2008). "A Jupiter-like Planet Orbiting the Nearby M Dwarf GJ832". The Astrophysical Journal 690 (1): 743–747. arXiv:0809.0172. Bibcode 2009ApJ...690..743B. doi:10.1088/0004-637X/690/1/743.
- ^ a b c Perryman, M. A. C. et al. (1997), "The Hipparcos Catalogue", Astronomy & Astrophysics 323: L49–L52, Bibcode 1997A&A...323L..49P
- ^ Johnson, H. M.; Wright, C. D. (1983). "Predicted infrared brightness of stars within 25 parsecs of the sun". Astrophysical Journal Supplement Series 53: 643–771. Bibcode 1983ApJS...53..643J. doi:10.1086/190905.
- ^ Interpolated value from NASA Exoplanet Archive, per:
Bessell, M. S. (August 10-12, 1994). "The Bottom of the Main Sequence - and Beyond". In Christopher G. Tinney. Proceedings of the ESO Workshop. Garching, Germany: Springer-Verlag Berlin Heidelberg New York. Bibcode 1995bmsb.conf..123B. - ^ Schmitt, J.H.M.M.; Fleming, T.A.; Giampapa M.S. (September 1995). "The X-ray view of the low-mass stars in the solar neighborhood". Astrophysical Journal 450 (9): 392–400. Bibcode 1995ApJ...450..392S. doi:10.1086/176149.
Coordinates: 
21h 33m 33.9752s, −49° 00′ 32.422″
|
|||||||||||||||||||||||||||||||||||||||||||||||||||
|
|||||||||||
 |
This main sequence star-related article is a stub. You can help Wikipedia by expanding it. |
