| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Taurus |
| Right ascension | 04 13 56.38482 |
| Declination | +09° 15′ 49.7729″ |
| Apparent magnitude (V) | 4.89 (5.05 + 7.32) |
| Characteristics | |
| Spectral type | G5III + A7V: |
| U−B color index | +0.46 |
| B−V color index | +0.82 |
| Astrometry | |
| Radial velocity (Rv) | -8.2 ± 0.4 km/s |
| Proper motion (μ) | RA: -10.31 mas/yr Dec.: -30.01 mas/yr |
| Parallax (π) | 9.83 ± 0.64 mas |
| Distance | 330 ± 20 ly (102 ± 7 pc) |
| Orbit | |
| Period (P) | 479 yr |
| Semi-major axis (a) | 1.053″ |
| Eccentricity (e) | 0.910 |
| Inclination (i) | 128.6° |
| Longitude of the node (Ω) | 52.9° |
| Periastron epoch (T) | B 1816.6 |
| Argument of periastron (ω) (secondary) | 263.0° |
| Details | |
| 47 Tau A | |
| Radius | 12.9 R☉ |
| Surface gravity (log g) | 2.67 ± 0.11 cgs |
| Temperature | 5117 ± 58 K |
| Metallicity | -0.10 ± 0.08 dex |
| Other designations | |
| BD+08° 652, HD 26722, HIP 19740, HR 1311, SAO 111674 | |
| Database references | |
| SIMBAD | 47 Tau |
| 47 Tau A | |
| 47 Tau B | |
47 Tauri (abbreviated to 47 Tau) is a binary star in the zodiac constellation of Taurus. Parallax measurements made by the Hipparcos spacecraft put it at a distance of about 330 light-years (102 parsecs) from Earth. The system has a combined apparent magnitude of about 4.89, meaning it can be faintly seen with the naked eye, according to the Bortle scale.
47 Tauri is a visual binary, meaning that the two components can be resolved, and the orbit is derived from the positions of the two stars. The primary component is a G-type giant. Its radius is about 13 times that of the Sun. The companion is likely a white-colored A-type main-sequence star that is fainter. The two stars are separated about 1.3 arcseconds away, and because of their large separation, the two stars take some 479 years to complete an orbit.
References
- ^ van Leeuwen, F.; et al. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.
- ^ "* 47 Tau". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2 May 2017.
- ^ "Sixth Catalog of Orbits of Visual Binary Stars". United States Naval Observatory. Archived from the original on 1 August 2017. Retrieved 2 May 2017.
- Stephenson, C. B.; Sanwal, N. B. (1969). "The masses of stars above the main sequence". The Astronomical Journal. 74: 689. Bibcode:1969AJ.....74..689S. doi:10.1086/110845.
- ^ Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode:1986EgUBV........0M.
- ^ Kang, Wonseok; Lee, Sang-Gak; Kim, Kang-Min (2011). "Abundances of Refractory Elements for G-Type Stars with Extrasolar Planets". The Astrophysical Journal. 736 (2): 87. arXiv:1105.3083. Bibcode:2011ApJ...736...87K. doi:10.1088/0004-637X/736/2/87. S2CID 118382154.
- ^ Pasinetti Fracassini, L. E.; et al. (2001). "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics". Astronomy & Astrophysics. 367 (2): 521–24. arXiv:astro-ph/0012289. Bibcode:2001A&A...367..521P. doi:10.1051/0004-6361:20000451. S2CID 425754.
