Gamma Muscae
Star in the constellation Musca
From Wikipedia, the free encyclopedia
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.[2] 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[1] |
| Declination | −72° 07′ 58.7597″[1] |
| Apparent magnitude (V) | 3.87[2] |
| Characteristics | |
| Evolutionary stage | main sequence[3][4] |
| Spectral type | B5 V[5] |
| U−B color index | −0.61[2] |
| B−V color index | −0.15[2] |
| Variable type | SPB |
| Astrometry | |
| Radial velocity (Rv) | 2.5±7.4[6] km/s |
| Proper motion (μ) | RA: −51.34[1] mas/yr Dec.: −5.40[1] mas/yr |
| Parallax (π) | 10.04±0.13 mas[1] |
| Distance | 325 ± 4 ly (100 ± 1 pc) |
| Absolute magnitude (MV) | −1.1[7] |
| Details | |
| Mass | 5.09[8] M☉ |
| Radius | 4.17[8] R☉ |
| Luminosity | 790[7] L☉ |
| Surface gravity (log g) | 3.87[8] cgs |
| Temperature | 15,490[8] K |
| Rotational velocity (v sin i) | 205[5] km/s |
| Age | 67.7[8] Myr |
| Other designations | |
| γ Mus, CD−70°997, FK5 487, GC 17672, HD 109026, HIP 61199, HR 4773, SAO 257000 | |
| Database references | |
| SIMBAD | data |
This is a B-type main-sequence star with a stellar classification of B5 V.[5] 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.[10] It is around five times as massive as the Sun.[11] 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.[5]
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.[7]