Mu Librae
μ Librae (Latinised as Mu Librae) is the Bayer designation for a probable triple star system in the zodiac constellation of Libra. They have a combined apparent visual magnitude of 5.32, which is bright enough to be faintly visible to the naked eye. With an annual parallax shift of 13.71 mas, the system is located at an estimated distance of around 240 light years.
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Libra |
| Right ascension | 14h 49m 19.05130s |
| Declination | −14° 08′ 56.4766″ |
| Apparent magnitude (V) | 5.32 (5.69 + 6.72 + 14.70) |
| Characteristics | |
| Spectral type | A1pSrCrEu + A6m |
| B−V color index | +0.07 |
| Astrometry | |
| Radial velocity (Rv) | −3.2±1.4 km/s |
| Proper motion (μ) | RA: −65.95 mas/yr Dec.: −14.54 mas/yr |
| Parallax (π) | 13.71 ± 0.69 mas |
| Distance | 240 ± 10 ly (73 ± 4 pc) |
| Absolute magnitude (MV) | 1.32±0.20 |
| Details | |
| μ Lib A | |
| Mass | 2.31±0.12 M☉ |
| Radius | 2.59 R☉ |
| Luminosity | 41.7 L☉ |
| Temperature | 9,592±260 K |
| Rotational velocity (v sin i) | 29.0±1.7 km/s |
| Age | 417 Myr |
| μ Lib B | |
| Radius | 2.59 R☉ |
| Rotational velocity (v sin i) | 32.0±6 km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
The inner pair consists of two A-type stars that, as of 2006, had an angular separation of 1.79 arc seconds along a position angle of 5.5°. They have an estimated physical separation of 139 AU. The primary, component A, is a visual magnitude 5.69 magnetic Ap star showing overabundances of the elements aluminum, strontium, chromium, and europium. Hence, it has a stellar classification of A1pSrEuCr. It is a photometric variable with periods of 25.3992±0.1970 d and 1.8871±0.0008 d. The surface magnetic field strength is 1,375 Gauss.
The secondary, component B, is an Am star with a stellar classification of A6m. It has a visual magnitude of 6.72. The tertiary member, component C, is a magnitude 14.70 star at an angular separation of 12.90 arc seconds along a position angle of 294°, as of 2000.