| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Boötes |
| Right ascension | 15 08 23.78241 |
| Declination | +26° 18′ 04.1464″ |
| Apparent magnitude (V) | 5.67 |
| Characteristics | |
| Spectral type | K2 III |
| U−B color index | +1.24 |
| B−V color index | +1.240±0.015 |
| Astrometry | |
| Radial velocity (Rv) | +19.31±0.30 km/s |
| Proper motion (μ) | RA: +4.454 mas/yr Dec.: −15.185 mas/yr |
| Parallax (π) | 6.8288 ± 0.0883 mas |
| Distance | 478 ± 6 ly (146 ± 2 pc) |
| Absolute magnitude (MV) | −0.31 |
| Orbit | |
| Period (P) | 2,567.1±0.6 d |
| Semi-major axis (a) | 11.2 mas |
| Eccentricity (e) | 0.8315±0.0027 |
| Inclination (i) | 62° |
| Longitude of the node (Ω) | 82.6±6.6° |
| Periastron epoch (T) | 2,448,356.6 JD |
| Argument of periastron (ω) (secondary) | 175.3±0.7° |
| Semi-amplitude (K1) (primary) | 9.25±0.10 km/s |
| Details | |
| 46 Boo A | |
| Radius | 23.35+0.85 −0.67 R☉ |
| Luminosity | 175.8±2.8 L☉ |
| Temperature | 4,349+64 −76 K |
| Metallicity | −0.27±0.15 dex |
| Other designations | |
| b Boo, 46 Boo, BD+26°2656, FK5 1396, GC 20367, HD 134320, HIP 74087, HR 5638, SAO 83682 | |
| Database references | |
| SIMBAD | data |
46 Boötis is a binary star system in the northern constellation of Boötes, located mid-way between α Coronae Borealis and ε Boötis. It has the Bayer designation b Boötis; 46 Boötis is the Flamsteed designation. The system lies 478 light-years away from the Sun based on parallax, and is visible to the naked eye as a faint, orange-hued star with a combined apparent visual magnitude of 5.67. It is moving away from the Earth with a heliocentric radial velocity of +19 km/s. The light from this system displays an unusually high level of polarization due to interstellar dust.
This is a single-lined spectroscopic binary with an orbital period of 7.03 years and a large eccentricity of 0.83. The primary member, designated component A, is an aging giant star with a stellar classification of K2 III. As a consequence of exhausting the hydrogen at its core, it has expanded to 23 times the Sun's radius. It is radiating 176 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,349 K. The companion star, component B, is most likely a lower main-sequence star with 0.6–0.8 times the Sun's mass.
References
- ^ Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
- ^ Sato, K.; Kuji, S. (November 1990), "MK classification and photometry of stars used for time and latitude observations at Mizusawa and Washington", Astronomy and Astrophysics Supplement Series, 85 (3): 1069–1087, Bibcode:1990A&AS...85.1069S.
- Guetter, H. H.; Hewitt, A. V. (1984), "Photoelectric UBV photometry for 317 PZT and VZT stars", Astronomical Society of the Pacific, 96: 441–443, Bibcode:1984PASP...96..441G, doi:10.1086/131362.
- ^ Griffin, R. F.; Eitter, J. J. (December 1999), "Spectroscopic binary orbits from photoelectric radial velocities. Paper 149: 46 Bootis", The Observatory, 119: 320–328, Bibcode:1999Obs...119..320G.
- ^ Jancart, S.; et al. (October 2005), "Astrometric orbits of SB^9 stars", Astronomy and Astrophysics, 442 (1): 365–380, arXiv:astro-ph/0507695, Bibcode:2005A&A...442..365J, doi:10.1051/0004-6361:20053003, S2CID 15123997.
- Taylor, Benjamin J. (June 1991), "A Critical Appraisal of Published Values of for K II--IV Stars", Astrophysical Journal Supplement, 76: 715, Bibcode:1991ApJS...76..715T, doi:10.1086/191579
- ^ "b Boo". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved May 12, 2019.
