| Observation data Epoch J2000 Equinox J2000 |
|
|---|---|
| Constellation | Lacerta |
| Right ascension | 22h 39m 15.67864s |
| Declination | +39° 03′ 00.9712″ |
| Apparent magnitude (V) | 4.880 |
| Characteristics | |
| Spectral type | O9V |
| U−B color index | −1.010 |
| B−V color index | −0.210 |
| Variable type | β Cep? |
| Astrometry | |
| Radial velocity (Rv) | −10.10 km/s |
| Proper motion (μ) |
RA: −0.32 mas/yr Dec.: −5.46 mas/yr |
| Parallax (π) | 1.89 ± 0.22mas |
| Distance | 715pc |
| Absolute magnitude (MV) | −4.40 |
| Details | |
| Mass | 26.9 M☉ |
| Radius | 8.27 R☉ |
| Luminosity | 102,000 L☉ |
| Surface gravity (log g) | 4.03 cgs |
| Temperature | 36,000 K |
| Rotational velocity (v sin i) | 35 km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
10 Lacertae (10 Lac) is a star in the constellation Lacerta. With an apparent magnitude is 4.9, it is located around 700 parsecs (2,300 ly) distant in the small Lacerta OB1 association. It is a hot blue main-sequence star of spectral type O9V, a massive star that is currently fusing its core hydrogen. It is a suspected Beta Cephei variable star.
10 Lacertae was one of the first O-type stars (along with S Monocerotis) to be defined as an anchor point for the MKK spectral classification; since the early twentieth century it has served as such a point. Specifically, the star is representative of O9V stars, meaning relatively cool O-type stars on the main-sequence.
10 Lacertae has an 8th magnitude companion about one arc-minute away.