32 Orionis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Orion |
| Right ascension | 05h 30m 47.05091s |
| Declination | +05° 56′ 53.2925″ |
| Apparent magnitude (V) | 4.20 (4.43 + 5.80) |
| Characteristics | |
| Spectral type | B5V + ? + B7V |
| U−B color index | –0.56 |
| B−V color index | –0.13 |
| Astrometry | |
| Radial velocity (Rv) | +18.60 km/s |
| Proper motion (μ) | RA: +5.10 mas/yr Dec.: –33.30 mas/yr |
| Parallax (π) | 10.77±0.64 mas |
| Distance | 300 ± 20 ly (93 ± 6 pc) |
| Absolute magnitude (MV) | –0.63 |
| Orbit | |
| Primary | A |
| Companion | B |
| Period (P) | 3000±430 years |
| Semi-major axis (a) | 3.46±0.41″ |
| Eccentricity (e) | 0.63±0.18 |
| Inclination (i) | 99±1° |
| Longitude of the node (Ω) | 41±1° |
| Periastron epoch (T) | 1970±107 |
| Argument of periastron (ω) (secondary) | 311±63° |
| Details | |
| 32 Ori A | |
| Mass | 5.0 M☉ |
| Radius | 2.9 R☉ |
| Luminosity | 388 L☉ |
| Surface gravity (log g) | 4.40 cgs |
| Temperature | 16,020 K |
| Rotational velocity (v sin i) | 169 km/s |
| Age | 65 Myr |
| Other designations | |
| A Ori, 32 Ori, NSV 14617, BD+05°939, GC 6813, HD 36267, HIP 25813, HR 1839, SAO 112849, CCDM J05308+0557AB, WDS J05308+0557AB | |
| Database references | |
| SIMBAD | data |
32 Orionis is a triple star system in the equatorial constellation of Orion. It has the Bayer designation A Orionis, while 32 Orionis is the Flamsteed designation. This system is visible to the naked eye as a faint point of light with a combined apparent visual magnitude of 4.20. It is located approximately 303 light-years away from the Sun based on parallax, and is drifting further away with a radial velocity of +18.6 km/s.
The system is a member of the eponymous 32 Orionis group, a young, nearby association of 46 co-moving stars first discovered in 2007. Research in 2015 suggested that Bellatrix is a probable member of the group due to its distance and position in the sky and suggested it be called the Bellatrix Cluster, although further research in 2017 called Bellatrix's membership into question due to its proper motion deviating significantly from the group.
The primary component of this system is a B-type main-sequence star with a stellar classification of B5V and a magnitude around 4.43. This is actually a spectroscopic binary with an orbital period of 3.964 days and eccentricity of 0.38. The unseen companion has an estimated mass of 0.6 times that of the Sun. Component B, at an angular separation of 1.08″ from the primary, is a class B7V star with a magnitude of 5.8, orbiting with the primary at a period of 3,000 years and eccentricity 0.63.