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Gliese 832

Coordinates: Sky map 21h 33m 33.9752s, −49° 00′ 32.422″
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Gliese 832
Gliese 832 is located in the constellation Grus.
Gliese 832 is located in the constellation Grus.
Gliese 832
Location of Gliese 832 in the constellation Grus

Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Grus
Right ascension 21h 33m 33.97512s[1]
Declination −49° 00′ 32.3994″[1]
Apparent magnitude (V) 8.66[2]
Characteristics
Evolutionary stage main-sequence star
Spectral type M2V[3]
B−V color index 1.52[2]
Astrometry
Radial velocity (Rv)12.72±0.13[1] km/s
Proper motion (μ) RA: −45.917 mas/yr[1]
Dec.: −816.875 mas/yr[1]
Parallax (π)201.3252 ± 0.0237 mas[1]
Distance16.200 ± 0.002 ly
(4.9671 ± 0.0006 pc)
Absolute magnitude (MV)10.19[2]
Details
Mass0.441 ± 0.011[4] M
Radius0.442 ± 0.018[4] R
Luminosity (bolometric)0.0276 ± 0.0009 [4] L
Luminosity (visual, LV)0.007[note 1] L
Surface gravity (log g)4.7[2] cgs
Temperature3,539+79
−74
[4] K
Metallicity [Fe/H]−0.06 ± 0.04[5] dex
Rotation37.5+1.4
−1.5
 d
[6]
Age6±1.5[6] Gyr
Other designations
CD−49°13515, GJ 832, HD 204961, HIP 106440, L 354-89, LHS 3685, PLX 5190, TIC 139754153, TYC 8431-60-1, 2MASS J21333397-4900323[7]
Database references
SIMBADThe star
planet c
planet b
Exoplanet Archivedata
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.[8] 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 818.16 milliarcseconds per year.[1] Gliese 832 has just under half the mass and radius of the Sun.[8] Its estimated rotation period is a relatively leisurely 46 days.[3] The star is roughly 6 billion years old.[6]

This star achieved perihelion some 52,920 years ago when it came within an estimated 15.71 ly (4.817 pc) of the Sun.[9]

Gliese 832 emits X-rays.[10] Despite the strong flare activity, Gliese 832 is producing on average less ionizing radiation than the Sun. Only at extremely short radiation wavelengths (<50nm) does its radiation intensity rise above the level of quiet Sun, but does not reach levels typical for active Sun.[11]

Planetary system

[edit]

Gliese 832 hosts one known planet, with a second planet having been refuted in 2022.[6] No additional planets were found as of 2024.[12]

The Gliese 832 planetary system[13]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(years)
Eccentricity Inclination Radius
b 0.8+0.12
−0.11
 MJ
3.53+0.15
−0.16
9.88+0.34
−0.33
0.069+0.026
−0.027
54.9+6.6
−4.9
or 125.1+4.9
−6.6
°

Gliese 832 b

[edit]

In September 2008, it was announced that a Jupiter-like planet, designated Gliese 832 b, had been detected in a long-period, near-circular orbit around this star, with a false alarm probability of 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] The orbital solution of the planet was refined in 2011.[14] In 2023, an astrometric detection of the planet was announced, determining its inclination and revealing a true mass 80% the mass of Jupiter.[13]

Gliese 832 c

[edit]

Gliese 832 c was believed to be of super-Earth mass.[8] It was announced to orbit in the optimistic habitable zone but outside the conservative habitable zone of its parent star.[15] The planet Gliese 832 c was believed to be in, or very close to, the right distance from its sun to allow liquid water to exist on its surface.[8] However, doubts were raised about the existence of planet c by a 2015 study, which found that its orbital period is close to the stellar rotation period.[3] The existence of the planet was refuted in 2022, when a study found that the radial velocity signal shows characteristics of a signal originating from stellar activity, and not from a planet.[6]

The region between Gliese 832 b and where Gliese 832 c would be is a zone where additional planets are possible.[16]

Search for cometary disc

[edit]

If this system has a comet disc, it is not "brighter than the fractional dust luminosity 10−5" according to a 2012 Herschel study.[17]

See also

[edit]

Notes

[edit]
  1. ^ Using the absolute visual magnitude of Gliese 832 and the absolute visual magnitude of the Sun , the visual luminosity can be calculated by

References

[edit]
  1. ^ a b c d e f g Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  2. ^ a b c d e f 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. S2CID 17172233.
  3. ^ a b c 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, S2CID 119181646.
  4. ^ a b c d Pineda, J. Sebastian; Youngblood, Allison; France, Kevin (September 2021). "The M-dwarf Ultraviolet Spectroscopic Sample. I. Determining Stellar Parameters for Field Stars". The Astrophysical Journal. 918 (1): 23. arXiv:2106.07656. Bibcode:2021ApJ...918...40P. doi:10.3847/1538-4357/ac0aea. S2CID 235435757. 40.
  5. ^ 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. S2CID 119216828. Archived from the original on 2021-01-23. Retrieved 2018-09-03.
  6. ^ a b c d e Gorrini, P.; Astudillo-Defru, N.; et al. (August 2022). "Detailed stellar activity analysis and modelling of GJ 832: Reassessment of the putative habitable zone planet GJ 832c". Astronomy & Astrophysics. 664: A64. arXiv:2206.07552. Bibcode:2022A&A...664A..64G. doi:10.1051/0004-6361/202243063. S2CID 249674385.
  7. ^ "Gliese 832". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-09-23.
  8. ^ a b c d "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 Archived 2018-07-12 at the Wayback Machine
  9. ^ 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, S2CID 59039482, A35.
  10. ^ 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.
  11. ^ Fontenla, J. M.; Linsky, Jeffrey L.; Garrison, Jesse; France, Kevin; Buccino, A.; Mauas, Pablo; Vietes, Mariela; Walkowicz, Lucianne M. (2016). "Semi-Empirical Modeling of the Photosphere, Chromopshere, Transition Region, and Corona of the M-Dwarf Host Star Gj 832". The Astrophysical Journal. 830 (2): 154. arXiv:1608.00934. Bibcode:2016ApJ...830..154F. doi:10.3847/0004-637X/830/2/154. hdl:11336/21732. S2CID 119279568.
  12. ^ https://arxiv.org/abs/2409.01173
  13. ^ a b Xiao, Guang-Yao; Liu, Yu-Juan; et al. (March 2023). "The Masses of a Sample of Radial-Velocity Exoplanets with Astrometric Measurements". Research in Astronomy and Astrophysics. 23 (5). arXiv:2303.12409. Bibcode:2023RAA....23e5022X. doi:10.1088/1674-4527/accb7e. S2CID 257663647.
  14. ^ Bonfils, Xavier; Delfosse, Xavier; Udry, Stéphane; Forveille, Thierry; Mayor, Michel; Perrier, Christian; Bouchy, François; Gillon, Michaël; Lovis, Christophe; Pepe, Francesco; Queloz, Didier; Santos, Nuno C.; Ségransan, Damien; Bertaux, Jean-Loup (2011). "The HARPS search for southern extra-solar planets XXXI. The M-dwarf sample". Astronomy and Astrophysics. 549: A109. arXiv:1111.5019. Bibcode:2013A&A...549A.109B. doi:10.1051/0004-6361/201014704. S2CID 119288366.
  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. S2CID 12157837.
  16. ^ Satyal, S.; Griffith, J.; Musielak, Z. E. (2016), "Dynamics of a Probable Earth-mass Planet in GJ 832 System", The Astrophysical Journal, 845 (2): 106, arXiv:1604.04544, doi:10.3847/1538-4357/aa80e2, S2CID 118663957
  17. ^ 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. S2CID 53704989.