HR 6902

HR 6902

Visible, blue and ultraviolet light curves for an eclipse of V2291 Ophiuchi, adapted from Griffin et al. (1995)
Observation data
Epoch J2000      Equinox J2000
Constellation Ophiuchus
Right ascension 18h 25m 38.799s
Declination +08° 01 55.23
Apparent magnitude (V) +5.64
Characteristics
Spectral type G9IIb / B8V
Variable type Zeta Aurigae-type
Astrometry
Proper motion (μ) RA: −3.920 mas/yr
Dec.: −6.549 mas/yr
Parallax (π)3.7061±0.1604 mas
Distance880 ± 40 ly
(270 ± 10 pc)
Absolute magnitude (MV)–1.33
Orbit
Period (P)1.055 yr
Semi-major axis (a)1.96 AU
Eccentricity (e)0.311
Inclination (i)87°
Details
Mass3.86/2.95 M
Radius33/3 R
Luminosity562/146 L
Temperature4,900/11,600 K
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
SIMBADdata

HR 6902 (also designated V2291 Oph) is a binary system located 880 light years away 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.