46 Boötis
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Boötes |
Right ascension | 15h 08m 23.78241s[1] |
Declination | +26° 18′ 04.1464″[1] |
Apparent magnitude (V) | 5.67[2] |
Characteristics | |
Spectral type | K2 III[3] |
U−B color index | +1.24[4] |
B−V color index | +1.240±0.015[2] |
Astrometry | |
Radial velocity (Rv) | +19.31±0.30[2] km/s |
Proper motion (μ) | RA: +4.454[1] mas/yr Dec.: −15.185[1] mas/yr |
Parallax (π) | 6.8288 ± 0.0883 mas[1] |
Distance | 478 ± 6 ly (146 ± 2 pc) |
Absolute magnitude (MV) | −0.31[2] |
Orbit[5] | |
Period (P) | 2,567.1±0.6 d |
Semi-major axis (a) | 11.2 mas[6] |
Eccentricity (e) | 0.8315±0.0027 |
Inclination (i) | 62[6]° |
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[5]° |
Semi-amplitude (K1) (primary) | 9.25±0.10[5] km/s |
Details | |
46 Boo A | |
Radius | 23.35+0.85 −0.67[1] R☉ |
Luminosity | 175.8±2.8[1] L☉ |
Temperature | 4,349+64 −76[1] K |
Metallicity [Fe/H] | −0.27±0.15[7] dex |
Other designations | |
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.[5] It has the Bayer designation b Boötis; 46 Boötis is the Flamsteed designation.[8] The system lies 478 light-years away from the Sun based on parallax,[1] and is visible to the naked eye as a faint, orange-hued star with a combined apparent visual magnitude of 5.67.[2] It is moving away from the Earth with a heliocentric radial velocity of +19 km/s.[2] The light from this system displays an unusually high level of polarization due to interstellar dust.[5]
This is a single-lined spectroscopic binary with an orbital period of 7.03 years and a large eccentricity of 0.83.[5] The primary member, designated component A, is an aging giant star with a stellar classification of K2 III.[3] As a consequence of exhausting the hydrogen at its core, it has expanded to 23[1] times the Sun's radius. It is radiating 176[1] times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,349 K.[1] The companion star, component B, is most likely a lower main-sequence star with 0.6–0.8 times the Sun's mass.[6]
References
[edit]- ^ a b c d e f g h i j k l 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.
- ^ a b c d e f 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.
- ^ a b 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.
- ^ a b c d e f 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.
- ^ a b c 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 [Fe/H] for K II--IV Stars", Astrophysical Journal Supplement, 76: 715, Bibcode:1991ApJS...76..715T, doi:10.1086/191579
- ^ a b "b Boo". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved May 12, 2019.