Gliese 208

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Gliese 208
Observation data
Epoch J2000      Equinox J2000
Constellation Orion
Right ascension 05h 36m 30.991s[1]
Declination +11° 19′ 40.33″[1]
Apparent magnitude (V) 8.80 - 9.05[2]
Spectral type M0.0 Ve[3]
Variable type RS CVn[2]
Radial velocity (Rv) 21.772[4] km/s
Proper motion (μ) RA: −2.811 ± 0.080[1] mas/yr
Dec.: −56.368 ± 0.060[1] mas/yr
Parallax (π) 87.66 ± 0.29[1] mas
Distance 37.2 ± 0.1 ly
(11.41 ± 0.04 pc)
Absolute magnitude (MV) 8.6
Mass 0.646[5] M
Radius 0.601[5] R
Luminosity 0.08[6] L
Temperature 3,966[5] K
Metallicity [Fe/H] +0.05[5] dex
Age 2.7[5] Gyr
Other designations
Gliese 208, Gj 208, V2689 Orionis, BD+11°878, HIP 26335, HD 245409, TYC 709-63-1, SAO 94695
Database references

Gliese 208 (Gj 208) is a red dwarf star with an apparent magnitude of 8.9. It is in the constellation of Orion 37 light years away.

The spectral type of Gj 208 has variously been described between K6 and M1.[7][8][9] Two of the most recent observations give a statistically calculated spectral type of K7.9[5] or a more traditional classification of M0.0 Ve.[3] It is a cool dwarf star and probably a spectroscopic binary.[2]

Calculations from 2010 suggest that this star passed as close as 1.537 parsecs (5.0 light-years) from the Sun about 500,000 years ago.[10]

Gj 208 is an RS Canum Venaticorum variable, close binary systems which show small amplitude brightness changes caused by chromospheric activity. Its visual magnitude varies by about a quarter magnitude with a period of 12.285 days.[2]


  1. ^ a b c d e Gaia Collaboration (2016). "VizieR Online Data Catalog: Gaia DR1 (Gaia Collaboration, 2016)". VizieR On-line Data Catalog: I/337. Originally published in: Astron. Astrophys. 1337. Bibcode:2016yCat.1337....0G. 
  2. ^ a b c d Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/gcvs. Originally published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S. 
  3. ^ a b Lépine, Sébastien; Hilton, Eric J.; Mann, Andrew W.; Wilde, Matthew; Rojas-Ayala, Bárbara; Cruz, Kelle L.; Gaidos, Eric (2013). "A Spectroscopic Catalog of the Brightest (J < 9) M Dwarfs in the Northern Sky". The Astronomical Journal. 145 (4): 102. Bibcode:2013AJ....145..102L. doi:10.1088/0004-6256/145/4/102. 
  4. ^ Soubiran, C.; Jasniewicz, G.; Chemin, L.; Crifo, F.; Udry, S.; Hestroffer, D.; Katz, D. (2013). "The catalogue of radial velocity standard stars for Gaia. I. Pre-launch release". Astronomy & Astrophysics. 552: A64. Bibcode:2013A&A...552A..64S. doi:10.1051/0004-6361/201220927. 
  5. ^ a b c d e f Mann, Andrew W.; Feiden, Gregory A.; Gaidos, Eric; Boyajian, Tabetha; von Braun, Kaspar (2015). "How to Constrain Your M Dwarf: Measuring Effective Temperature, Bolometric Luminosity, Mass, and Radius". The Astrophysical Journal. 804: 64. arXiv:1501.01635Freely accessible. Bibcode:2015ApJ...804...64M. doi:10.1088/0004-637X/804/1/64. 
  6. ^ McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (2012). "Fundamental parameters and infrared excesses of Hipparcos stars". Monthly Notices of the Royal Astronomical Society. 427: 343. Bibcode:2012MNRAS.427..343M. doi:10.1111/j.1365-2966.2012.21873.x. 
  7. ^ Stephenson, C. B. (1986). "Dwarf K and M stars of high proper motion found in a hemispheric survey". Astronomical Journal. 92: 139. Bibcode:1986AJ.....92..139S. doi:10.1086/114146. 
  8. ^ Stephenson, C. B.; Sanduleak, N. (1975). "Dwarf K and M stars discovered on objective-prism plates". Astronomical Journal. 80: 972. Bibcode:1975AJ.....80..972S. doi:10.1086/111829. 
  9. ^ Skiff, B. A. (2014). "VizieR Online Data Catalog: Catalogue of Stellar Spectral Classifications (Skiff, 2009-2016)". VizieR On-line Data Catalog: B/mk. Originally published in: Lowell Observatory (October 2014). 1. Bibcode:2014yCat....1.2023S. 
  10. ^ Bobylev, Vadim V. (March 2010). "Searching for Stars Closely Encountering with the Solar System". Astronomy Letters. 36 (3): 220–226. arXiv:1003.2160Freely accessible. Bibcode:2010AstL...36..220B. doi:10.1134/S1063773710030060. 

External links[edit]

  • Wikisky image of HD 245409 (Gliese 208)