Gamma Tauri
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Taurus |
| Right ascension | 04h 19m 47.6037s |
| Declination | +15° 37′ 39.512″ |
| Apparent magnitude (V) | 3.654 |
| Characteristics | |
| Evolutionary stage | red clump |
| Spectral type | G8III |
| U−B color index | +0.84 |
| B−V color index | +0.99 |
| Astrometry | |
| Radial velocity (Rv) | 38.7 ± 0.9 km/s |
| Proper motion (μ) | RA: +115.29 mas/yr Dec.: -23.86 mas/yr |
| Parallax (π) | 21.17±1.17 mas |
| Distance | 154 ± 9 ly (47 ± 3 pc) |
| Absolute magnitude (MV) | 0.22 |
| Details | |
| Mass | 2.70 ± 0.13 M☉ |
| Radius | 13.4 ± 0.2 R☉ |
| Luminosity | 85 L☉ |
| Surface gravity (log g) | 2.58-2.61 cgs |
| Temperature | 4,844 ± 47 K |
| Metallicity [Fe/H] | +0.11 dex |
| Rotation | 253 days |
| Rotational velocity (v sin i) | 4 km/s |
| Age | 430–530 Myr |
| Other designations | |
| Prima Hyadum, Hyadum I, 54 Tauri, BD+15°612, FK5 159, HD 27371, HIP 20205, HR 1346, SAO 93868, GC 5226, WDS 04198+1538 | |
| Database references | |
| SIMBAD | data |
Gamma Tauri (γ Tauri, abbreviated Gamma Tau, γ Tau) is either a solitary, binary or double star (the Washington Double Star Catalog notes it as a "Dubious Double" or "Bogus Binary") that marks the tip of the "V" in the constellation of Taurus. It is a member of, and located within about 2.5 parsecs of the center of, the Hyades star cluster, the nearest open cluster to the Sun. Based upon parallax measurements, Gamma Tauri is approximately 154 light-years from the Sun.
Considered as a pair of stars, the two components are designated Gamma Tauri A (officially named Prima Hyadum /ˌpraɪmə ˈhaɪədəm/, the traditional name for the system) and B.