Gamma Muscae
γ Muscae, Latinised as Gamma Muscae, is a blue-white hued star in the southern circumpolar constellation of Musca, the Fly. It can be seen with the naked eye, having an apparent visual magnitude of 3.87. Based upon an annual parallax shift of 10.04 mas as seen from Earth, it is located about 325 light years from the Sun.
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Musca |
| Right ascension | 12h 32m 28.01343s |
| Declination | −72° 07′ 58.7597″ |
| Apparent magnitude (V) | 3.87 |
| Characteristics | |
| Spectral type | B5 V |
| U−B color index | −0.61 |
| B−V color index | −0.15 |
| Variable type | SPB |
| Astrometry | |
| Radial velocity (Rv) | 2.5±7.4 km/s |
| Proper motion (μ) | RA: −51.34 mas/yr Dec.: −5.40 mas/yr |
| Parallax (π) | 10.04 ± 0.13 mas |
| Distance | 325 ± 4 ly (100 ± 1 pc) |
| Absolute magnitude (MV) | −1.1 |
| Details | |
| Mass | 5.09 M☉ |
| Radius | 4.17 R☉ |
| Luminosity | 790 L☉ |
| Surface gravity (log g) | 3.87 cgs |
| Temperature | 15,490 K |
| Rotational velocity (v sin i) | 205 km/s |
| Age | 67.7 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is a B-type main-sequence star with a stellar classification of B5 V. It is a variable star that ranges between magnitudes 3.84 and 3.86 over a period of 2.7 days, and is classed as a slowly pulsating B star. It is around five times as massive as the Sun. The star is spinning rapidly with a projected rotational velocity of 205 km/s. This is giving it an oblate shape with an equatorial bulge that is 7% larger than the polar radius.
Gamma Muscae is a proper motion member of the Lower Centaurus–Crux sub-group in the Scorpius–Centaurus OB association, the nearest such association of co-moving massive stars to the Sun.