HR 6902

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HR 6902
V2291OphLightCurve.png
Visible, blue and ultraviolet light curves for an eclipse of V2291 Ophiuchi, adapted from Griffin et al. (1995) [1]
Observation data
Epoch J2000       Equinox J2000
Constellation Ophiuchus
Right ascension 18h 25m 38.799s [2]
Declination +08° 01 55.23 [2]
Apparent magnitude  (V)+5.64 [3]
Characteristics
Spectral type G9IIb / B8V
Variable type Zeta Aurigae-type
Astrometry
Proper motion (μ)RA: -4.07 ± 0.54 [2]   mas/yr
Dec.: -6.34 ± 0.31 [2]   mas/yr
Parallax (π)4.14 ± 0.41  mas [2]
Distance 790 ± 80  ly
(240 ± 20  pc)
Absolute magnitude  (MV)–1.33 [3]
Details
Mass 3.86/2.95 [4]   M
Radius 33/3 [4]   R
Luminosity 562/146  L
Temperature 4900/11600 [4]   K
Orbit
Period (P)1.055 [4] yr
Semi-major axis (a)1.96 [4] AU
Eccentricity (e)0.311 [4]
Inclination (i)87 [4] °
Other designations
V2291 Oph, GSC 01023-02454, HD 169690, HD 169689, 2MASS J18253880+0801551, BD+07 3682, FK5 1478, PPM 165790, HIP 90313, SAO 123462
Database references
SIMBAD data

HR 6902 (also designated V2291 Oph) is a binary system located 790 light years away [2] from the Sun in the Ophiuchus constellation. The system includes an orange bright giant star and a B-type main sequence star, forming an eclipsing binary of Zeta Aurigae type. The system is also surrounded by a warm circumstellar envelope and the spectra show silicon and carbon absorption up to a distance of 3.3 giant radii. [4]

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References

  1. Griffin, R. E. M.; Marshall, K. P.; Griffin, R. F.; Schroeder, K. P. (September 1995). "Optical spectra of ζ Aurigae binary systems. VII. The 1987 and 1989 eclipses of HR 6902". Astronomy and Astrophysics. 301: 217–230. Bibcode:1995A&A...301..217G . Retrieved 4 February 2022.
  2. 1 2 3 4 5 6 van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv: 0708.1752 . Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID   18759600. Vizier catalog entry
  3. 1 2 Jasniewicz, G.; et al. (February 1999), "Late-type giants with infrared excess. I. Lithium abundances", Astronomy and Astrophysics, 342: 831–838, Bibcode:1999A&A...342..831J
  4. 1 2 3 4 5 6 7 8 Kirsch; Baade, R.; Reimers, D. (2001). "The warm circumstellar envelope and wind of the G9 IIb star HR 6902". Astronomy and Astrophysics . 379 (3): 925–935. arXiv: astro-ph/0008378 . Bibcode:2001A&A...379..925K. doi:10.1051/0004-6361:20011117. S2CID   12157488.