BM Andromedae
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| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Andromeda |
| Right ascension | 23h 37m 38.49052s[2] |
| Declination | +48° 24′ 11.7624″[2] |
| Apparent magnitude (V) | 11.63 – 14.02[3] |
| Characteristics | |
| Spectral type | F8ea-K5Vea[3] |
| Apparent magnitude (B) | 12.40[4] |
| Apparent magnitude (V) | 12.40[5] |
| Apparent magnitude (G) | 12.76[2] |
| Apparent magnitude (J) | 10.524[6] |
| Apparent magnitude (H) | 9.523[6] |
| Apparent magnitude (K) | 8.810[6] |
| Variable type | T Tauri star[1] |
| Astrometry | |
| Radial velocity (Rv) | −12.37±3.96[2] km/s |
| Proper motion (μ) | RA: −5.249[2] mas/yr Dec.: +8.452[2] mas/yr |
| Parallax (π) | 1.2732±0.6439 mas[2] |
| Distance | approx. 3,000 ly (approx. 800 pc) |
| Details | |
| Luminosity (bolometric) | 5.5[7] L☉ |
| Other designations | |
| 2MASS J23373847+4824119, GSC 03642-00171 | |
| Database references | |
| SIMBAD | data |
BM Andromedae (BM And) is a T Tauri star in the constellation Andromeda. Its apparent visual magnitude has irregular variations between a maximum of 11.63 and a minimum of 14.02.[3]
The exact spectral class of the star is not yet known. Different estimations gives a range F8-K5Vea,[3] meaning that there is agreement in identifying it as a main sequence star more luminous and with stronger emission lines than the usual, a typical classification for young stars that are near the main sequence phase. The star is still accreting, and about 0.23 L☉ of 5.5 L☉ of its total luminosity is powered by accretion.[7]
The color indexes vary with the star's brightness, but the spectral class of BM Andromedae does not change with the decrease of luminosity. Strong H-alpha lines in the spectra are a sign of a gaseous envelope, while an infrared excess indicates the existence of an extended dust envelope.[1]
