Omega Lupi

Omega Lupi, Latinised from ω Lupi, is a double star in the southern constellation of Lupus. It is visible to the naked eye with an apparent visual magnitude of 4.33,^[2] showing up as a red-hued star just to the south of Gamma Lupi.^[10] Based upon an annual parallax shift of 8.97^[1] mas as seen from Earth, it is located around 360 light-years from the Sun.

Omega Lupi

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Lupus
Right ascension	15h 38m 03.20372s[1]
Declination	−42° 34′ 02.4444″[1]
Apparent magnitude (V)	4.33[2] (4.33 + 11.0)[3]
Characteristics
Spectral type	K4.5 III[4]
U−B color index	+1.72[2]
B−V color index	+1.43[2]
Astrometry
Radial velocity (Rv)	−6.8±2.7[5] km/s
Proper motion (μ)	RA: −21.37[1] mas/yr Dec.: −29.98[1] mas/yr
Parallax (π)	8.97±0.27 mas[1]
Distance	360 ± 10 ly (111 ± 3 pc)
Absolute magnitude (MV)	+0.21[6]
Details
A
Radius	22[7] R☉
Luminosity	122[7] L☉
Temperature	4,087[7] K
B
Radius	0.8[8] R☉
Luminosity	0.21[8] L☉
Surface gravity (log g)	4.56[8] cgs
Temperature	4,480[8] K
Other designations
ω Lup, CD−42°10601, FK5 3232, HD 139127, HIP 76552, HR 5797, SAO 226004[9]
Database references
SIMBAD	data

As of 2007, the components of this system had an angular separation of 11.4 arcseconds along a position angle of 29°,^[11] and are most likely gravitationally bound as a wide binary star system.^[3] The primary component is a magnitude 4.48 evolved giant star with a stellar classification of K4.5 III.^[4] The measured angular diameter, after correction for limb darkening, is 3.39±0.04 mas.^[12] At the estimated distance of Omega Lupi, this yields a physical size of about 40 times the radius of the Sun.^[13] The companion is a magnitude 11.0 star.^[3]