31 Boötis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Boötes |
| Right ascension | 14h 41m 38.75049s[1] |
| Declination | +08° 09′ 42.3409″[1] |
| Apparent magnitude (V) | 4.86[2] |
| Characteristics | |
| Spectral type | G7 IIIa[3] |
| B−V color index | 0.992±0.038[2] |
| Astrometry | |
| Radial velocity (Rv) | −16.5±1.8[2] km/s |
| Proper motion (μ) | RA: –9.589[1] mas/yr Dec.: +3.906[1] mas/yr |
| Parallax (π) | 6.8757 ± 0.2796 mas[1] |
| Distance | 470 ± 20 ly (145 ± 6 pc) |
| Absolute magnitude (MV) | −1.22[2] |
| Details | |
| Mass | 3.27[4] M☉ |
| Radius | 23.25+0.40 −0.49[1] R☉ |
| Luminosity | 274.9±12.6[1] L☉ |
| Surface gravity (log g) | 2.60[5] cgs |
| Temperature | 4,874+53 −41[1] K |
| Metallicity [Fe/H] | −0.10[5] dex |
| Rotational velocity (v sin i) | 6.5[6] km/s |
| Age | 370[4] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
31 Boötis is a single[8] star in the northern constellation of Boötes,[7] located 470 light years from the Sun.[1] It is visible to the naked eye as a faint, yellow-hued star with an apparent visual magnitude of 4.86.[2] The object is moving closer to the Earth with a heliocentric radial velocity of −16.5 km/s.[2] It was known to be part of a constellation between Virgo and Boötes named Mons Maenalus, it was also the brightest star in the constellation.
This is an evolved giant star with a stellar classification of G7 IIIa.[3] It is a suspected variable star of unknown type,[9] and is an X-ray source.[10] The star is 370[4] million years old with 3.27[4] times the mass of the Sun. Having exhausted the hydrogen at its core, the star has expanded to 23[1] times the Sun's radius. It is radiating 275[1] times the luminosity of the Sun from its swollen photosphere at an effective temperature of 4,874 K.[1]
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 Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins Catalog of Revised MK Types for the Cooler Stars", The Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373.
- ^ a b c d Luck, R. Earle (2015), "Abundances in the Local Region. I. G and K Giants", Astronomical Journal, 150 (3), 88, arXiv:1507.01466, Bibcode:2015AJ....150...88L, doi:10.1088/0004-6256/150/3/88, S2CID 118505114.
- ^ a b Hekker, S.; Meléndez, J. (2007), "Precise radial velocities of giant stars. III. Spectroscopic stellar parameters", Astronomy and Astrophysics, 475 (3): 1003, arXiv:0709.1145, Bibcode:2007A&A...475.1003H, doi:10.1051/0004-6361:20078233, S2CID 10436552.
- ^ De Medeiros, J. R.; et al. (November 2000), "Rotation and lithium in single giant stars", Astronomy and Astrophysics, 363: 239–243, arXiv:astro-ph/0010273, Bibcode:2000A&A...363..239D.
- ^ a b "31 Boo". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved May 10, 2019.
- ^ Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- ^ Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.
- ^ Haakonsen, Christian Bernt; Rutledge, Robert E. (September 2009), "XID II: Statistical Cross-Association of ROSAT Bright Source Catalog X-ray Sources with 2MASS Point Source Catalog Near-Infrared Sources", The Astrophysical Journal Supplement, 184 (1): 138–151, arXiv:0910.3229, Bibcode:2009ApJS..184..138H, doi:10.1088/0067-0049/184/1/138, S2CID 119267456.
