| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Perseus |
| Right ascension | 03h 25m 57.382s[2] |
| Declination | +49° 07′ 14.73″[2] |
| Apparent magnitude (V) | 6.09[3] |
| Characteristics | |
| Evolutionary stage | Main sequence |
| Spectral type | B7 V[4] |
| B−Vcolor index | −0.073±0.005[3] |
| Variable type | SPB[5] |
| Astrometry | |
| Radial velocity (Rv) | −1.5±0.9[6] km/s |
| Proper motion (μ) | RA: +23.753mas/yr[2] Dec.: −26.656mas/yr[2] |
| Parallax (π) | 6.0959±0.0444 mas[2] |
| Distance | 535 ± 4 ly (164 ± 1 pc) |
| Absolute magnitude (MV) | −0.19[3] |
| Details | |
| Mass | 3.69+0.14 −0.15[5] M☉ |
| Radius | 2.21[7] R☉ |
| Luminosity | 278.0+53.1 −44.7[5] L☉ |
| Surface gravity (log g) | 4.30[4] cgs |
| Temperature | 14,768[4] K |
| Metallicity[Fe/H] | 0.0082+0.0053 −0.0032[5] dex |
| Rotational velocity (v sin i) | 58[4] km/s |
| Age | 90[4] Myr |
| Other designations | |
| V576 Per,BD+48° 913,GC 4075,HD 21071,HIP 15988,HR 1029,SAO 38817[8] | |
| Database references | |
| SIMBAD | data |
HD 21071 is a blue-white huedvariable star in the northernconstellation ofPerseus. Also known asV576 Persei, it is a sixth magnitude star that is dimly visible to the naked eye under good viewing conditions, having anapparent visual magnitude of 6.09.[3] The brightness of the star varies with a multiperiodic cycle.[9] The distance to HD 21071, as determined from an annualparallax shift of6.1 mas,[2] is 535 light years. It is a member of the youngAlpha Persei Cluster, Melotte 20,[4][10] and moving is closer to the Earth with a heliocentricradial velocity of −1.5 km/s.[6]
This is aB-type main-sequence star with astellar classification of B7 V.[4] HD 21071 belongs to an unusual stellar population termed'sn' stars. These seem to be related tochemically peculiar stars, but have sharp ('s')Balmer andmetalabsorption lines with "broad coreless He I" ('n') lines. The latter wide, "nebulous" lines may be due toStark broadening caused by anelectric field.[4] HD 21071 is aslowly pulsating B-type star (SPB star) that was initially found to vary with a period of 0.84 days. Further study revealed four frequencies, with the two dominant, higheramplitude frequencies having similar cycles of 1.19 and 1.15 per day.[5]
| ID | Frequency (d−1) | V Amplitude (mmag) | Radial Velocity (km/s) |
|---|---|---|---|
| 1 | 1.18843 | 18.5 | 3.28±0.85 |
| 2 | 1.14934 | 7.7 | – |
| 3 | 1.41968 | 3.8 | – |
| 4 | 0.95706 | 3.0 | – |
Stellar models show the star to have 3.7[5] times themass of the Sun, with 2.21[7] times theSun's radius. It is 90[4] million years old with a near-solarmetallicity and is spinning with aprojected rotational velocity of 58 km/s.[4] The star is radiating 278[5] times theSun's luminosity from itsphotosphere at aneffective temperature of 14,768 K.[4]
