67 Ophiuchi (67 Oph) is a class B5 Ib[3] (blue supergiant) star in the constellation Ophiuchus. Its apparent magnitude is 3.93[2] and it is approximately 1200 light years away based on parallax.[1] It is considered to be a member of the open cluster Collinder 359 (Melotte 186).
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Ophiuchus |
Right ascension | 18h 00m 38.71619s[1] |
Declination | 2° 55′ 53.6324″[1] |
Apparent magnitude (V) | 3.93[2] |
Characteristics | |
Spectral type | B5Ib[3] |
U−B color index | -0.62[2] |
B−V color index | +0.03[2] |
Astrometry | |
Radial velocity (Rv) | -5.20[4] km/s |
Proper motion (μ) | RA: +1.15[1] mas/yr Dec.: -9.35[1] mas/yr |
Parallax (π) | 2.65 ± 0.54 mas[1] |
Distance | approx. 1,200 ly (approx. 380 pc) |
Absolute magnitude (MV) | -3.50[5] |
Details | |
Mass | 8.4[6] M☉ |
Luminosity | 2364[5] L☉ |
Surface gravity (log g) | 3.03[7] cgs |
Temperature | 15,420[8] K |
Metallicity [Fe/H] | -0.01[7] dex |
Rotational velocity (v sin i) | 40[9] km/s |
Other designations | |
Database references | |
SIMBAD | data |
67 Oph has four companions. The closest is a magnitude 13.7 B1 main sequence star at 8.29", designated B. Component C (BD+02°3459) is the brightest close companion, a magnitude 8.1 B2 main sequence star at 54.32". Component D is a magnitude 12.5 star 8.37" from component C. Component E is a magnitude 10.9 star 46.53" from 67 Oph A.[10]
This star was once considered part of the obsolete constellation Taurus Poniatovii, but after the International Astronomical Union officially recognized constellations, it was placed in Ophiuchus.[11]