Beta Muscae
Star in the constellation Musca / From Wikipedia, the free encyclopedia
Beta Muscae, Latinized from β Muscae, is a binary star in the southern circumpolar constellation of Musca. With a combined apparent visual magnitude of 3.07,[2] it is the second brightest star (or star system) in the constellation. Judging by the parallax results, it is located at a distance of roughly 340 ± 13 light-years (105 ± 4 parsecs) from the Earth.[1]
Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Musca |
Right ascension | 12h 46m 16.80410s[1] |
Declination | –68° 06′ 29.2164″[1] |
Apparent magnitude (V) | 3.05 (3.51 + 4.01)[2] |
Characteristics | |
Spectral type | B2 V + B3 V[2] |
U−B color index | –0.766[3] |
B−V color index | –0.198[3] |
Astrometry | |
Radial velocity (Rv) | +42[4] km/s |
Proper motion (μ) | RA: –41.97[1] mas/yr Dec.: –8.89[1] mas/yr |
Parallax (π) | 9.55 ± 0.41 mas[1] |
Distance | 340 ± 10 ly (105 ± 4 pc) |
Absolute magnitude (MV) | −2.06[5] |
Orbit[6] | |
Period (P) | 194.28 yr |
Semi-major axis (a) | 0.969″ |
Eccentricity (e) | 0.598 |
Inclination (i) | 37.1° |
Longitude of the node (Ω) | 349.4° |
Periastron epoch (T) | 1857.50 |
Argument of periastron (ω) (secondary) | 209.0° |
Details | |
β Mus A | |
Mass | 7.35[7] M☉ |
Luminosity | 1,892[5] L☉ |
Age | 15.1 ± 1.2[8] Myr |
β Mus B | |
Mass | 6.40[7] M☉ |
Other designations | |
Database references | |
SIMBAD | data |
This is a binary star system with a period of about 194 years at an orbital eccentricity of 0.6.[6] As of 2007, the two stars had an angular separation of 1.206 arcseconds at a position angle of 35°.[7] The components are main sequence stars of similar size and appearance. The primary component, β Muscae A, has an apparent magnitude of 3.51, a stellar classification of B2 V,[2] and about 7.35 times the Sun's mass.[7] The secondary component, β Muscae B, has an apparent magnitude of 4.01, a stellar classification of B3 V,[2] and is about 6.40 times the mass of the Sun.[7]
This is a confirmed member of the Scorpius–Centaurus association,[2][7] which is a group of stars with similar ages, locations, and trajectories through space, implying that they formed together in the same molecular cloud. Beta Muscae is considered a runaway star system as it has a high peculiar velocity of 43.9 km s−1 relative to the normal galactic rotation. Runaway stars can be produced through several means, such as through an encounter with another binary star system. Binary systems form a relatively small fraction of the total population of runaway stars.[10]