HD 34626, also known as MZ Aurigae, is an unusual variable star in the northern constellationofAuriga. It has an apparent magnitude of 8.2 and is about 3,300 light years away.
| |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Auriga |
| Right ascension | 05h20m 33.03590s[2] |
| Declination | +36° 37′ 56.0306″[2] |
| Apparent magnitude (V) | 8.16[3] |
| Characteristics | |
| Spectral type | B1.5 IVnp[4] |
| U−B color index | −0.68[5] |
| B−V color index | +0.03[5] |
| Variable type | SX Ari?[6] |
| Astrometry | |
| Radial velocity (Rv) | −6[7] km/s |
| Proper motion (μ) | RA: −0.630[2] mas/yr Dec.: −4.017[2] mas/yr |
| Parallax (π) | 0.9831 ± 0.0356 mas[2] |
| Distance | 3,300 ± 100 ly (1,020 ± 40 pc) |
| Details | |
| Mass | 4.4[2] M☉ |
| Radius | 21[2] R☉ |
| Luminosity | 556[2] L☉ |
| Temperature | 22,675[3] K |
| Rotational velocity (v sin i) | 310[8] km/s |
| Age | 200[9] Myr |
| Other designations | |
MZ Aurigae, MZ Aur, BD+36°1090, HD 34626, HIP 24938, SAO 57915. | |
| Database references | |
| SIMBAD | data |
The spectrum of HD 34626 had long been known to be unusual, with very broad lines indicating rapid rotation and emission lines marking it as a Be star. In 1970, it was found to vary in brightness by 0.1 magnitude over time scales of 8 to 12 hours, but these variations are not periodic.[10] This indicates the variability is not caused by ellipsoidal effects, and the nature of the variability remains unknown.[8] It may be a type of SX Arietis variable.[6]
HD 34626 has exhausted its core hydrogen and evolved away from the main sequence. Its spectral type indicates that it is a subgiant, but evolutionary models suggest it may be in the giant stage.[2]
