Mu Persei
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Perseus |
| Right ascension | 04h 14m 53.86253s |
| Declination | +48° 24′ 33.5912″ |
| Apparent magnitude (V) | +4.16 |
| Characteristics | |
| Spectral type | G0Ib + B9.5 |
| B−V color index | 0.935±0.002 |
| Astrometry | |
| Radial velocity (Rv) | 26.46 km/s |
| Proper motion (μ) | RA: 5.52 mas/yr Dec.: −17.37 mas/yr |
| Parallax (π) | 3.62±0.20 mas |
| Distance | 900 ± 50 ly (280 ± 20 pc) |
| Absolute magnitude (MV) | −3.08 |
| Orbit | |
| Period (P) | 284 d |
| Semi-major axis (a) | 18.8 ± 8.8 mas |
| Eccentricity (e) | 0.062 |
| Inclination (i) | 74 ± 24° |
| Longitude of the node (Ω) | 296 ± 18° |
| Periastron epoch (T) | 2,420,062 |
| Argument of periastron (ω) (secondary) | 302° |
| Details | |
| Radius | ~53 R☉ |
| Luminosity | ~2030 L☉ |
| Surface gravity (log g) | 1.74 cgs |
| Temperature | 5418 K |
| Metallicity [Fe/H] | 0.09 dex |
| Rotational velocity (v sin i) | 12 km/s |
| Other designations | |
| Mu Per, μ Per, 51 Persei, NSV 1518, BD+48 1063, FK5 1117, GC 5099, HD 26630, HIP 19812, HR 1303, SAO 39404, PPM 46912, CCDM J04149+4824A, WDS J04149+4825A | |
| Database references | |
| SIMBAD | data |
Mu Persei, Latinised from μ Persei, is a binary star system in the northern constellation of Perseus. It is visible to the naked eye as a point of light with a combined apparent visual magnitude of +4.16. The distance to this system is approximately 900 light-years based on parallax measurements. It is drifting further away with a radial velocity of +26 km/s.
Mu Persei is a spectroscopic binary with an orbital period of 284 days and an eccentricity of about 0.06. The primary component is a yellow G-type supergiant star. With an effective temperature of about 5,400 K and a radius of 53 solar radii, this star has the luminosity of about 2,030 times that of the Sun. The companion is a B-type star with a class of B9.5
Mu Persei is moving through the galaxy at a speed of 35.6 km/s relative to the Sun. Its projected galactic orbit carries it between 23,900 and 32,400 light-years from the center of the galaxy.
Mu Persei came closest to the Sun 5.6 million years ago when it had brightened to magnitude 3.25 from a distance of 600 light-years.