Omega Lupi
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Lupus |
| Right ascension | 15h 38m 03.20372s |
| Declination | −42° 34′ 02.4444″ |
| Apparent magnitude (V) | 4.33 (4.33 + 11.0) |
| Characteristics | |
| Spectral type | K4.5 III |
| U−B color index | +1.72 |
| B−V color index | +1.43 |
| Astrometry | |
| Radial velocity (Rv) | −6.8±2.7 km/s |
| Proper motion (μ) | RA: −21.37 mas/yr Dec.: −29.98 mas/yr |
| Parallax (π) | 8.97±0.27 mas |
| Distance | 360 ± 10 ly (111 ± 3 pc) |
| Absolute magnitude (MV) | +0.21 |
| Details | |
| A | |
| Radius | 22 R☉ |
| Luminosity | 122 L☉ |
| Temperature | 4,087 K |
| B | |
| Radius | 0.8 R☉ |
| Luminosity | 0.21 L☉ |
| Surface gravity (log g) | 4.56 cgs |
| Temperature | 4,480 K |
| Other designations | |
| ω Lup, CD−42°10601, FK5 3232, HD 139127, HIP 76552, HR 5797, SAO 226004 | |
| Database references | |
| SIMBAD | data |
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, showing up as a red-hued star just to the south of Gamma Lupi. Based upon an annual parallax shift of 8.97 mas as seen from Earth, it is located around 360 light-years from the Sun.
As of 2007, the components of this system had an angular separation of 11.4 arcseconds along a position angle of 29°, and are most likely gravitationally bound as a wide binary star system. The primary component is a magnitude 4.48 evolved giant star with a stellar classification of K4.5 III. The measured angular diameter, after correction for limb darkening, is 3.39±0.04 mas. At the estimated distance of Omega Lupi, this yields a physical size of about 40 times the radius of the Sun. The companion is a magnitude 11.0 star.