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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 16.2 light years and has a high proper motion of 818.93 milliarcseconds 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.

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 emits X-rays. Despite of the strong Flare star, Gliese 832 is producing in average less ionizing radiation than the Sun. Only at extremely short radiation wavelengths (<50nm) its radiation intensity raises above level of quiet Sun, but do not reach levels typical for active Sun.

Planetary system

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. The orbital solution of the planet was refined in 2011.

In 2014, a second planet Gliese 832 c 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. The planet Gliese 832 c is believed to be in, or very close to, the right distance from its sun to allow liquid water to exist on its surface.

The region between Gliese 832 b and Gliese 832 c is a zone where additional planets are possible.

Search for cometary disc

If this system has a comet disc, it is undetectable "brighter than the fractional dust luminosity 10" of a recent Herschel study.

See also

• List of nearest stars
• List of extrasolar planets

Notes

1. Using the absolute visual magnitude of Gliese 832 ${\displaystyle \scriptstyle M_{V_{\ast }}=10.19}$ with a bolometric correction of ${\displaystyle \scriptstyle BC=-1.821}$ the bolometric magnitude can be calculated as ${\displaystyle \scriptstyle M_{bol_{\ast }}=8.369}$, the bolometric magnitude of the Sun ${\displaystyle \scriptstyle M_{bol_{\odot }}=4.73}$, and so therefore the bolometric luminosity can be calculated by ${\displaystyle \scriptstyle {\frac {L_{bol_{\ast }}}{L_{bol_{\odot }}}}=10^{0.4\left(M_{bol_{\odot }}-M_{bol_{\ast }}\right)}}$
2. Using the absolute visual magnitude of Gliese 832 ${\displaystyle \scriptstyle M_{V_{\ast }}=10.19}$ and the absolute visual magnitude of the Sun ${\displaystyle \scriptstyle M_{V_{\odot }}=4.83}$, the visual luminosity can be calculated by ${\displaystyle \scriptstyle {\frac {L_{V_{\ast }}}{L_{V_{\odot }}}}=10^{0.4\left(M_{V_{\odot }}-M_{V_{\ast }}\right)}}$

References

1. ^ Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
2. ^ Bailey, J.; Butler, R. P.; Tinney, C. G.; Jones, H. R. A.; O'Toole, S.; Carter, B. D.; Marcy, G. W. (2009). "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.
3. ^ Suárez Mascareño, A.; et al. (September 2015), "Rotation periods of late-type dwarf stars from time series high-resolution spectroscopy of chromospheric indicators", Monthly Notices of the Royal Astronomical Society, 452 (3): 2745–2756, arXiv:1506.08039, Bibcode:2015MNRAS.452.2745S, doi:10.1093/mnras/stv1441.{{citation}}: CS1 maint: unflagged free DOI (link)
4. Johnson, H. M.; Wright, C. D. (1983). "Predicted infrared brightness of stars within 25 parsecs of the sun". The Astrophysical Journal Supplement Series. 53: 643–771. Bibcode:1983ApJS...53..643J. doi:10.1086/190905.
5. Flower, Phillip J. (September 1996). "Transformations from Theoretical Hertzsprung-Russell Diagrams to Color-Magnitude Diagrams: Effective Temperatures, B-V Colors, and Bolometric Corrections". The Astrophysical Journal. 469: 355. Bibcode:1996ApJ...469..355F. doi:10.1086/177785.
6. Torres, Guillermo (November 2010). "On the Use of Empirical Bolometric Corrections for Stars". The Astronomical Journal. 140 (5): 1158–1162. arXiv:1008.3913. Bibcode:2010AJ....140.1158T. doi:10.1088/0004-6256/140/5/1158. {{cite journal}}: Unknown parameter |layurl= ignored (help)
7. Interpolated value from NASA Exoplanet Archive, per: Bessell, M. S. (1995). "The Temperature Scale for Cool Dwarfs". In Tinney, C. G. (ed.). The Bottom of the Main Sequence - and Beyond, Proceedings of the ESO Workshop. Springer-Verlag. p. 123. Bibcode:1995bmsb.conf..123B. {{cite conference}}: Unknown parameter |booktitle= ignored (|book-title= suggested) (help)
8. Lindgren, Sara; Heiter, Ulrike (2017). "Metallicity determination of M dwarfs. Expanded parameter range in metallicity and effective temperature". Astronomy and Astrophysics. 604: A97. arXiv:1705.08785. Bibcode:2017A&A...604A..97L. doi:10.1051/0004-6361/201730715.
9. ^ Safonova, M.; Murthy, J.; Shchekinov, Yu. A. (2014). "Age Aspects of Habitability". International Journal of Astrobiology. 15 (2): 93–105. arXiv:1404.0641. Bibcode:2016IJAsB..15...93S. doi:10.1017/S1473550415000208.
10. "Gliese 832". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-09-23.
11. ^ "Nearby Alien Planet May Be Capable of Supporting Life", Mike Wall, Space.com, June 25, 2014, http://www.space.com/26357-exoplanet-habitable-zone-gliese-832c.html
12. ^ Bailer-Jones, C. A. L. (March 2015), "Close encounters of the stellar kind", Astronomy & Astrophysics, 575: 13, arXiv:1412.3648, Bibcode:2015A&A...575A..35B, doi:10.1051/0004-6361/201425221, A35.
13. Schmitt, J. H. M. M.; Fleming, T. A.; Giampapa, M. S. (1995). "The X-ray view of the low-mass stars in the solar neighborhood". The Astrophysical Journal. 450 (9): 392–400. Bibcode:1995ApJ...450..392S. doi:10.1086/176149.
14. SEMI-EMPIRICAL MODELING OF THE PHOTOSPHERE, CHROMOSPHERE, TRANSITION REGION, AND CORONA OF THE M-DWARF HOST STAR GJ 832, 2016, arXiv:1608.00934
15. ^ The HARPS search for southern extra-solar planets XXXI. The M-dwarf sample, 2011, arXiv:1111.5019
16. Wittenmyer, R.A.; Tuomi, M.; Butler, R.P.; Jones, H. R. A.; O'Anglada-Escude, G.; Horner, J.; Tinney, C.G.; Marshall, J.P.; Carter, B.D.; et al. (2014). "GJ 832c: A super-earth in the habitable zone". The Astrophysical Journal. 1406 (2): 5587. arXiv:1406.5587. Bibcode:2014ApJ...791..114W. doi:10.1088/0004-637X/791/2/114.
17. Dynamics of a Probable Earth-mass Planet in GJ 832 System, 2016, arXiv:1604.04544
18. B. C. Matthews; forthcoming study promised in Lestrade, J.-F.; Matthews, B. C.; Sibthorpe, B.; Kennedy, G. M.; Wyatt, M. C.; Bryden, G.; Greaves, J. S.; Thilliez, E.; Moro-Martín, A.; Booth, M.; Dent, W. R. F.; Duchêne, G.; Harvey, P. M.; Horner, J.; Kalas, P.; Kavelaars, J. J.; Phillips, N. M.; Rodriguez, D. R.; Su, K. Y. L.; Wilner, D. J. (2012). "A DEBRIS Disk Around The Planet Hosting M-star GJ581 Spatially Resolved with Herschel". Astronomy and Astrophysics. 548: A86. arXiv:1211.4898. Bibcode:2012A&A...548A..86L. doi:10.1051/0004-6361/201220325.

v t e Constellation of Grus
List of stars in Grus List of star names in Grus Grus in Chinese astronomy
Stars	Bayer α (Alnair) β (Tiaki) γ (Aldhanab) δ δ ε ζ η θ ι κ λ μ μ ν ξ ο π π ρ σ σ τ τ τ υ φ Variable RZ CE HR 8323 8501 HD 208487 (Itonda) 213240 215456 Other 2MASS J22282889–4310262 Gliese 832 PSR J2144−3933 S5-HVS1 WASP-95 WISE 2220−3628
Exoplanets Gliese 832 b HD 208487 b HD 213240 b τ Gruis b
Galaxies	NGC 7070 7070A 7072 7075 7079 7087 7213 7418 7424 7496 7531 7552 7582 7590 Other IC 1459 IC 5201
Galaxy clusters Abell S1063
Category

• Gliese 832
• Local Bubble
• M-type main-sequence stars
• Henry Draper Catalogue objects
• Hipparcos objects
• Grus (constellation)
• Durchmusterung objects
• Planetary systems with two confirmed planets