| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Perseus |
| Right ascension | 04h 33m 24.90304s[1] |
| Declination | +43° 03′ 50.0154″[1] |
| Apparent magnitude (V) | 6.078[2] |
| Characteristics | |
| Spectral type | F0 V[3] |
| U−Bcolor index | +0.01[4] |
| B−Vcolor index | +0.38[4] |
| Astrometry | |
| Radial velocity (Rv) | −23.0±4.3[5] km/s |
| Proper motion (μ) | RA: +5.370[1]mas/yr Dec.: +5.531[1]mas/yr |
| Parallax (π) | 16.3759±0.0181 mas[1] |
| Distance | 199.2 ± 0.2 ly (61.07 ± 0.07 pc) |
| Absolute magnitude (MV) | +2.23[6] |
| Details | |
| Mass | 1.28[7] M☉ |
| Radius | 2.6[1] R☉ |
| Luminosity | 11.0[1] L☉ |
| Surface gravity (log g) | 3.87[7] cgs |
| Temperature | 6,615±225[7] K |
| Metallicity[Fe/H] | −0.19[8] dex |
| Rotational velocity (v sin i) | 90[3] km/s |
| Age | 1.614[7] Gyr |
| Other designations | |
| m Per,57 Per,BD+42°990,FK5 1124,HD 28704,HIP 21242,HR 1434,SAO 39604,WDS J04334+4304A[9] | |
| Database references | |
| SIMBAD | data |
57 Persei, orm Persei, is a suspectedtriple star[10] system in the northernconstellation ofPerseus. It is at the lower limit of visibility to the naked eye, having a combinedapparent visual magnitude of 6.08.[2] The annualparallax shift of16.4 mas provides a distance measure of 199 light years. 57 Persei is moving closer to the Sun with aradial velocity of about −23[5] km/s and will makeperihelion in around 2.6 million years at a distance of roughly 22 ly (6.6 pc).[11]
The primary member, 57 Persei, is a magnitude 6.18,[10] yellow-white huedF-type main-sequence star with astellar classification of F0 V,[3] indicating it is generating energy by fusing itscorehydrogen. It is an estimated 1.6[7] billion years old and is spinning with aprojected rotational velocity of 90 km/s.[3] The star has 1.3[7] times themass of the Sun and is radiating 11 times theSun's luminosity from itsphotosphere at aneffective temperature of around6,615 K.[7]
An unseen companion has been identified via slight changes to theproper motion of the primary.[10] The third possible member of the system, designated component B,[12] is a magnitude 6.87F-type star at anangular separation of 120.13 arc seconds.[10] This star has a different parallax and space velocity than the primary,[13] so it may just be a widevisual companion.[12] There are three other nearby visual companions that are not physically associated with the 57 Persei system.[12]
