BM Scorpii
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Scorpius |
| Right ascension | 17h 40m 58.54640s |
| Declination | −32° 12′ 52.0644″ |
| Apparent magnitude (V) | 5.25 – 6.46 |
| Characteristics | |
| Spectral type | K2Ib Hδ1 |
| Variable type | SRd |
| Astrometry | |
| Radial velocity (Rv) | −7.39 km/s |
| Proper motion (μ) | RA: −0.895 mas/yr Dec.: −6.073 mas/yr |
| Parallax (π) | 2.0344±0.0681 mas |
| Distance | 1,600 ± 50 ly (490 ± 20 pc) |
| Absolute magnitude (MV) | −2.57 |
| Details | |
| Mass | 5-9 M☉ |
| Radius | 129 R☉ |
| Luminosity | 3,388 L☉ |
| Surface gravity (log g) | 1.1 cgs |
| Temperature | 3,888 K |
| Metallicity [Fe/H] | −0.22 dex |
| Other designations | |
| BM Sco, CD−32°13142, HD 160371, HIP 86527 | |
| Database references | |
| SIMBAD | data |
BM Scorpii (BM Sco) is a red supergiant and a semiregular variable star located in the constellation Scorpius. It lies approximately 490 parsecs (1,600 ly) away in the open cluster Messier 6, the Butterfly Cluster.