67 Ophiuchi

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 2,000 light years away based on spectroscopy.^[5] It is considered to be a member of the open cluster Collinder 359 (Melotte 186).

67 Ophiuchi

Location of 67 Ophiuchi (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Ophiuchus
Right ascension	18h 00m 38.71619s[1]
Declination	+02° 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	2,020±200 ly (620±60 pc)[5]
Absolute magnitude (MV)	−3.5[6]
Details
Mass	12.6±0.4[5] M☉
Radius	31±4[5] R☉
Luminosity	39,800+9,200 −7,500[5] L☉
Surface gravity (log g)	3.03[7] cgs
Temperature	14,700±300[5] K
Metallicity [Fe/H]	−0.01[7] dex
Rotational velocity (v sin i)	40[8] km/s
Age	16.6+1.6 −1.5[5] Myr
Other designations
BD+02°3458, CCDM J18007+0256A, FK5 677, GC 24509, HIP 88192, HR 6714, HD 164353, SAO 123013, WDS J18006+0256A
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.^[9]

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.^[10]