Omicron Tauri
Star in the constellation Taurus From Wikipedia, the free encyclopedia
Star in the constellation Taurus From Wikipedia, the free encyclopedia
ο Tauri, Latinized as Omicron Tauri, is a binary star system in the constellation Taurus, near the constellation border with Cetus. It has a yellow hue and is visible to the naked eye with an apparent visual magnitude of 3.61.[2] It is approximately 191 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −20 km/s.[1] As the westernmost bright point of light in Taurus, this system has the Flamsteed designation 1 Tauri; Omicron Tauri is the Bayer designation.[7]
 | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Taurus |
| Right ascension | 03h 24m 48.79146s[1] |
| Declination | +09° 01′ 43.9941″[1] |
| Apparent magnitude (V) | 3.61[2] |
| Characteristics | |
| Spectral type | G6 III[3] |
| B−V color index | +0.887±0.019[2] |
| Astrometry | |
| Radial velocity (Rv) | −19.79±0.06[1] km/s |
| Proper motion (μ) | RA: –59.776[1] mas/yr Dec.: –78.579[1] mas/yr |
| Parallax (π) | 17.1066 ± 0.3775 mas[1] |
| Distance | 191 ± 4 ly (58 ± 1 pc) |
| Absolute magnitude (MV) | −0.45[4] |
| Orbit[5] | |
| Period (P) | 1654.9 d |
| Eccentricity (e) | 0.26 |
| Periastron epoch (T) | 2429974.34 JD |
| Argument of periastron (ω) (secondary) | 155.6° |
| Semi-amplitude (K1) (primary) | 4.4 km/s |
| Details | |
| ο Tauri A | |
| Mass | 3.01[4] M☉ |
| Radius | 18.10+1.45 −6.63[1] R☉ |
| Luminosity | 149.4±3.7[1] L☉ |
| Surface gravity (log g) | 2.52[4] cgs |
| Temperature | 5,180[4] K |
| Metallicity [Fe/H] | –0.12[4] dex |
| Rotational velocity (v sin i) | 25 ± 2[6] km/s |
| Age | 380[4] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is a single-lined spectroscopic binary[5] system with the two components orbiting each other over a period of 4.53 years with an eccentricity of 0.263.[8] The visible component is an aging G-type giant with a stellar classification of G6 III.[3] This star has three[4] times the mass of the Sun and eighteen[1] times the Sun's radius. Based on the latter, interferometry-measured radius, it is rotating once every 533 days.[9] It is radiating 149[1] times the luminosity of the Sun from its photosphere at an effective temperature of 5,180 K.[4]
