HD 50138
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Monoceros |
| Right ascension | 06h 51m 33.399s |
| Declination | −06° 57′ 59.45″ |
| Apparent magnitude (V) | 6.58 |
| Characteristics | |
| Spectral type | B6-7III-V[e] |
| B−V color index | 0.030±0.008 |
| Variable type | γ Cas or FS CMa |
| Astrometry | |
| Radial velocity (Rv) | 40.8±0.2 km/s |
| Proper motion (μ) | RA: −3.678 mas/yr Dec.: 4.178 mas/yr |
| Parallax (π) | 2.8487±0.0459 mas |
| Distance | 1,140 ± 20 ly (351 ± 6 pc) |
| Absolute magnitude (MV) | 0.22 |
| Details | |
| Mass | 6 M☉ |
| Radius | 7.0±2.1 R☉ |
| Luminosity | (1.2±0.4)×103 L☉ |
| Surface gravity (log g) | 4.63±0.16 cgs |
| Temperature | 6,391±241 13,000 K |
| Metallicity [Fe/H] | 0.18±0.04 dex |
| Rotational velocity (v sin i) | 1.81389 km/s |
| Other designations | |
| MWC 158, V743 Mon, BD−06°1775, GC 8983, HD 50138, HIP 32923, SAO 133781, PPM 189615 | |
| Database references | |
| SIMBAD | data |
HD 50138 is a peculiar star in the equatorial constellation of Monoceros, the unicorn. It has the variable star designation V743 Monocerotis. The typical apparent visual magnitude of this star is 6.58, placing it near the lower limit for visibility to the naked eye. Based on parallax measurements, this star is located at a distance of approximately 1,140 light years. It is drifting further away with a heliocentric radial velocity of 41 km/s. This is an isolated star, being located far from any star forming region and having a low proper motion.