Gamma Velorum
Gamma Velorum is a quadruple star system in the constellation Vela. This name is the Bayer designation for the star, which is Latinised from γ Velorum and abbreviated γ Vel. At a combined magnitude of +1.72, it is one of the brightest stars in the night sky, and contains by far the closest and brightest Wolf–Rayet star. It has the traditional name Suhail al Muhlif and the modern name Regor /ˈriːɡɔːr/, but neither is approved by the International Astronomical Union, this makes it the brightest star by apparent magnitude to remain without an IAU approved name.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Vela |
| Right ascension | 08h 09m 31.95013s |
| Declination | –47° 20′ 11.7108″ |
| Apparent magnitude (V) | 1.83 (1.81–1.87) |
| Characteristics | |
| Spectral type | WC8 + O7.5III |
| U−B color index | −0.94 |
| B−V color index | −0.25 |
| Variable type | Wolf–Rayet |
| Astrometry | |
| Radial velocity (Rv) | +12 ± 1 km/s |
| Proper motion (μ) | RA: –6.07 mas/yr Dec.: +10.43 mas/yr |
| Parallax (π) | 2.92 ± 0.30 mas |
| Distance | 1096+26 −23 ly (336+8 −7 pc) |
| Absolute magnitude (MV) | −4.6 + −6.0 |
| Orbit | |
| Primary | O |
| Companion | WR |
| Period (P) | 78.53 ± 0.01 days |
| Semi-major axis (a) | 1.2 AU |
| Eccentricity (e) | 0.326 ± 0.01 |
| Inclination (i) | 65 ± 8° |
| Periastron epoch (T) | 2,450,120.5 ± 2 |
| Argument of periastron (ω) (secondary) | 248 ± 4° |
| Semi-amplitude (K1) (primary) | 38.4 ± 2 km/s |
| Semi-amplitude (K2) (secondary) | 122 ± 2 km/s |
| Details | |
| WR | |
| Mass | 9.0 ± 0.6 M☉ |
| Radius | 1.9 R☉ |
| Luminosity (bolometric) | 204,000 L☉ |
| Luminosity (visual, LV) | 5,900 L☉ |
| Temperature | 90,000 K |
| Age | 5 Myr |
| O | |
| Mass | 28.5 ± 1.1 M☉ |
| Radius | 16.2 R☉ |
| Luminosity (bolometric) | 363,000 L☉ |
| Luminosity (visual, LV) | 21,500 L☉ |
| Temperature | 35,100 K |
| Age | 5 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Vela |
| Right ascension | 08h 09m 29.3260s |
| Declination | –47° 20′ 43.027″ |
| Apparent magnitude (V) | 4.27 |
| Characteristics | |
| Spectral type | B2III |
| U−B color index | −0.92 |
| B−V color index | −0.22 |
| Astrometry | |
| Radial velocity (Rv) | +9.7 ± 1 km/s |
| Proper motion (μ) | RA: –0.6 mas/yr Dec.: +9.7 mas/yr |
| Absolute magnitude (MV) | −3.62 |
| Details | |
| Mass | 14 M☉ |
| Age | 8 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
The γ Velorum system includes a pair of stars separated by 41″, each of which is also a spectroscopic binary system. γ2 Velorum, the brighter of the visible pair, contains the Wolf–Rayet star and a blue supergiant, while γ1 Velorum contains a blue giant and an unseen companion.