| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Taurus |
| Right ascension | 02h12m 22.28003s[1] |
| Declination | +30° 18′ 11.0430″[1] |
| Apparent magnitude (V) | +5.51[2] |
| Characteristics | |
| Spectral type | K2 III[2] |
| B−V color index | 1.077[2] |
| Astrometry | |
| Radial velocity (Rv) | +24.75±0.02[2] km/s |
| Proper motion (μ) | RA: −65.05[1] mas/yr Dec.: −60.50[1] mas/yr |
| Parallax (π) | 11.22 ± 0.70 mas[1] |
| Distance | 290 ± 20 ly (89 ± 6 pc) |
| Absolute magnitude (MV) | +0.76[2] |
| Details | |
| Mass | 1.53[3] M☉ |
| Radius | 12[4] R☉ |
| Luminosity | 57.5[3] L☉ |
| Surface gravity (log g) | 2.5[5] cgs |
| Temperature | 4,737±77[3] K |
| Metallicity [Fe/H] | 0.12[5] dex |
| Rotational velocity (v sin i) | 4.6[4] km/s |
| Age | 4.21[3] Gyr |
| Other designations | |
ω1 Tau, 43 Tau, BD+19° 672, FK5 1115, HD 26162, HIP 19388, HR 1283, SAO 93785[6] | |
| Database references | |
| SIMBAD | data |
Omega1 Tauri is a solitary,[7] orange hued star in the zodiac constellationofTaurus. It is faintly visible to the naked eye with an apparent visual magnitude of +5.51.[2] Based upon an annual parallax shift of 11.22 mas as seen from Earth,[1] it is located about 290 light years from the Sun.
This is an evolved K-type giant star with a stellar classification of K2 III.[2] At the estimated age of 4.2 billion years,[3] it is a red clump star that is generating energy by helium fusion at its core.[5] Omega1 Tauri has about 1.5[3] times the mass of the Sun and has expanded to around 12[4] times the Sun's radius. It is radiating 57.5 times the Sun's luminosity from its photosphere at an effective temperature of 4,737 K.[3] The radial velocity of this star shows no appreciable variation, and for this reason it is used as a radial velocity standard.[2]
