Gliese 832

Gliese 832
Observation data; Epoch J2000.0 Equinox J2000.0
Constellation	Grus
Right ascension	21h 33m 33.9750s[1]
Declination	−49° 00′ 32.4035″[1]
Apparent magnitude (V)	8.66[2]
Characteristics
Spectral type	M2V[3]
B−V color index	1.52[2]
Astrometry
Radial velocity (Rv)	18.0 km/s
Proper motion (μ)	RA: −45.834±0.071[1] mas/yr ; Dec.: −816.604±0.064[1] mas/yr
Parallax (π)	201.4073 ± 0.0429[1] mas
Distance	16.194 ± 0.003 ly ; (4.965 ± 0.001 pc)
Absolute magnitude (MV)	10.19[2]
Details
Mass	0.45 ± 0.05[2] M☉
Radius	0.48[4] R☉
Luminosity (bolometric)	0.035[note 1] L☉
Luminosity (visual, LV)	0.007[note 2] L☉
Surface gravity (log g)	4.7[2] cgs
Temperature	3,620[7] K
Metallicity [Fe/H]	−0.06±0.04[8] dex
Rotation	45.7±9.3 d[3]
Age	9.24[9] Gyr
Other designations
	CD-49°13515, HD 204961, HIP 106440, LHS 3685, PLX 5190[10]
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.[11] The apparent visual magnitude of 8.66[2] 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[1] and has a high proper motion of 818.93 milliarcseconds[12] per year.[1] Gliese 832 has just under half the mass and radius of the Sun.[11] Its estimated rotation period is a relatively leisurely 46 days.[3] The star is roughly 9.5 billion years old.[9]

In 2014, Gliese 832 was announced to be hosting the closest potentially habitable Earth-mass-range exoplanet to the Solar System.[11] This star achieved perihelion some 52,920 years ago when it came within an estimated 15.71 ly (4.817 pc) of the Sun.[12]

Planetary system

Gliese 832 hosts two known planets.

Discovery of Jupiter mass planet

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.[2]

Discovery of Gliese 832 c (super-Earth mass planet) in habitable zone

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[11] and has since been given the scientific name Gliese 832 c.[11] It was announced to orbit in the optimistic habitable zone but outside the conservative habitable zone of its parent star.[13]

The planet is believed to be in, or very close to, the right distance from its sun to allow liquid water to exist on its surface.[11]

Search for cometary disc

If this system has a comet disc, it is undetectable "brighter than the fractional dust luminosity 10⁻⁵" of a recent Herschel study.[14]

The Gliese 832 planetary system
Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
c	≥5.4±1 M_⊕	0.162±0-017	35.68±0.03	0.18 ± 0.13	—	—
b	≥0.64 ± 0.06 M_J	3.4 ± 0.4	3416 ± 131	0.12 ± 0.11	—	—

X-ray source

Gliese 832 emits X-rays.[15]

Notes

Using the absolute visual magnitude of Gliese 832 $\scriptstyle M_{V_{\ast }}=10.19$ with a bolometric correction of $\scriptstyle BC=-1.821$ [5] the bolometric magnitude can be calculated as $\scriptstyle M_{bol_{\ast }}=8.369$ , the bolometric magnitude of the Sun $\scriptstyle M_{bol_{\odot }}=4.73$ ,[6] and so therefore the bolometric luminosity can be calculated by $\scriptstyle {\frac {L_{bol_{\ast }}}{L_{bol_{\odot }}}}=10^{0.4\left(M_{bol_{\odot }}-M_{bol_{\ast }}\right)}$
Using the absolute visual magnitude of Gliese 832 $\scriptstyle M_{V_{\ast }}=10.19$ and the absolute visual magnitude of the Sun $\scriptstyle M_{V_{\odot }}=4.83$ , the visual luminosity can be calculated by $\scriptstyle {\frac {L_{V_{\ast }}}{L_{V_{\odot }}}}=10^{0.4\left(M_{V_{\odot }}-M_{V_{\ast }}\right)}$

References

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.
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.
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.
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.
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.
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. Lay summary.
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.
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.
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.
"Gliese 832". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-09-23.
"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
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.
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.
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.
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.

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[luminosity_bolometric-7] Using the absolute visual magnitude of Gliese 832 $\scriptstyle M_{V_{\ast }}=10.19$ with a bolometric correction of $\scriptstyle BC=-1.821$ [5] the bolometric magnitude can be calculated as $\scriptstyle M_{bol_{\ast }}=8.369$ , the bolometric magnitude of the Sun $\scriptstyle M_{bol_{\odot }}=4.73$ ,[6] and so therefore the bolometric luminosity can be calculated by $\scriptstyle {\frac {L_{bol_{\ast }}}{L_{bol_{\odot }}}}=10^{0.4\left(M_{bol_{\odot }}-M_{bol_{\ast }}\right)}$

[luminosity_visual-8] Using the absolute visual magnitude of Gliese 832 $\scriptstyle M_{V_{\ast }}=10.19$ and the absolute visual magnitude of the Sun $\scriptstyle M_{V_{\odot }}=4.83$ , the visual luminosity can be calculated by $\scriptstyle {\frac {L_{V_{\ast }}}{L_{V_{\odot }}}}=10^{0.4\left(M_{V_{\odot }}-M_{V_{\ast }}\right)}$

[Gaia_DR2-1] 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.

[bailey08-2] 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.

[mnras452_3_2745-3] 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.

[apjss53_643-4] 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.

[citation-bolometric_correction-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.

[citation-tableprovisoBC-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. Lay summary.

[bessell1994-9] 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.

[Lindgren2017-10] 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.

[age-11] 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.

[Simbad-12] "Gliese 832". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-09-23.

[Mike_Wall-13] "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

[aa575_A35-14] 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.

[Wittenmyer14-15] 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.

[nodebris-16] 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.

[Schmitt-17] 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.