Omicron Lupi
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Lupus |
| Right ascension | 14h 51m 38.30289s |
| Declination | −43° 34′ 31.2965″ |
| Apparent magnitude (V) | 4.323 (4.84 + 5.27) |
| Characteristics | |
| Spectral type | B5 IV |
| U−B color index | −0.620 |
| B−V color index | −0.159 |
| Astrometry | |
| Radial velocity (Rv) | +7.30±0.74 km/s |
| Proper motion (μ) | RA: −25.20 mas/yr Dec.: −27.13 mas/yr |
| Parallax (π) | 8.07±0.59 mas |
| Distance | 400 ± 30 ly (124 ± 9 pc) |
| Absolute magnitude (MV) | −1.2±0.3 |
| Details | |
| Mass | 5.7±0.2 M☉ |
| Radius | 3.5 R☉ |
| Luminosity | 1,260 L☉ |
| Surface gravity (log g) | 4.1±0.1 cgs |
| Temperature | 18,000 K |
| Rotational velocity (v sin i) | 25 km/s |
| Other designations | |
| ο Lup, CD−43°9391, HD 130807, HIP 72683, HR 5528, SAO 225248 | |
| Database references | |
| SIMBAD | data |
Omicron Lupi (ο Lup) is a binary star in the southern constellation of Lupus. It is a visible to the naked eye with a combined apparent visual magnitude of 4.323. Based upon an annual parallax shift of 8.07 mas as seen from Earth, it is located around 400 light-years from the Sun, give or take 30 light-years. At that distance, the visual magnitude of the system is diminished by an extinction factor of 0.13±0.01 due to interstellar dust. It is a member of the Upper Centaurus–Lupus subgroup of the nearby Scorpius–Centaurus association.
This is a visual binary star system with the components having an angular separation of 0.1 arcsecond. The primary, component A, is a magnitude 4.84 B-type subgiant star with a stellar classification of B5 V. It displays radial velocity variations indicating it has an unseen second companion orbiting at a separation of at least 17 AU with a period of 27 years or more. The spectrum of the primary displays a Zeeman effect indicating a magnetic field with a strength ranging from −94 to 677 G. The visible companion, component B, has a visual magnitude of 5.27.