40 Boötis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Boötes |
| Right ascension | 14h 59m 36.94745s[1] |
| Declination | +39° 15′ 55.1994″[1] |
| Apparent magnitude (V) | 5.64[2] |
| Characteristics | |
| Evolutionary stage | giant[3] |
| Spectral type | F1 III–IV[4] |
| B−V color index | 0.336±0.004[2] |
| Astrometry | |
| Radial velocity (Rv) | +12.3±0.7[5] km/s |
| Proper motion (μ) | RA: −32.109[1] mas/yr Dec.: 41.246[1] mas/yr |
| Parallax (π) | 19.5911 ± 0.0702 mas[1] |
| Distance | 166.5 ± 0.6 ly (51.0 ± 0.2 pc) |
| Absolute magnitude (MV) | 2.08[2] |
| Details | |
| Mass | 1.47[6] M☉ |
| Radius | 2.35+0.34 −0.13[1] R☉ |
| Luminosity | 11.585±0.054[1] L☉ |
| Surface gravity (log g) | 3.88[6] cgs |
| Temperature | 7,070±240[6] K |
| Metallicity [Fe/H] | −0.29[5] dex |
| Rotational velocity (v sin i) | 72.5[3] km/s |
| Age | 1.166[6] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
40 Boötis is a single[8] star located 166.5 light years away from the Sun in the northern constellation of Boötes. It is visible to the naked eye as a dim, yellow-white hued star with an apparent visual magnitude of 5.64.[2] The star is moving away from the Earth with a heliocentric radial velocity of +12 km/s.[5]
The Hipparcos catalogue (1997) lists a stellar classification of F1 III–IV,[9] matching the luminosity class of an aging star that is evolving into a giant.[3] Earlier, Cowley and Bidelman (1979) listed a class of F2 III,[10] while Sato and Kuji (1990) found a main sequence class of F0V.[11] It is around 1.2[6] billion years old with a relatively high rotation rate, showing a projected rotational velocity of 72.5 km/s.[3] The star has 1.5[6] times the mass of the Sun and 2.4[1] times the Sun's radius. It is radiating 11.6[1] times the luminosity of the Sun from its photosphere at an effective temperature of 7,070 K.[6]
References[edit]
- ^ a b c d e f g h i 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 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 c d Schröder, C.; Reiners, Ansgar; Schmitt, Jürgen H. M. M. (January 2009), "Ca II HK emission in rapidly rotating stars. Evidence for an onset of the solar-type dynamo" (PDF), Astronomy and Astrophysics, 493 (3): 1099–1107, Bibcode:2009A&A...493.1099S, doi:10.1051/0004-6361:200810377[permanent dead link]
- ^ Boro Saikia, S.; et al. (2018), "Chromospheric activity catalogue of 4454 cool stars. Questioning the active branch of stellar activity cycles", Astronomy and Astrophysics, 616: A108, arXiv:1803.11123, Bibcode:2018A&A...616A.108B, doi:10.1051/0004-6361/201629518, S2CID 118915212.
- ^ a b c Casagrande, L.; et al. (2011), "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey", Astronomy and Astrophysics, 530: A138, arXiv:1103.4651, Bibcode:2011A&A...530A.138C, doi:10.1051/0004-6361/201016276, S2CID 56118016.
- ^ a b c d e f g David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.
- ^ "40 Boo". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved May 12, 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.
- ^ ESA (1997), "The HIPPARCOS and TYCHO catalogues. Astrometric and photometric star catalogues derived from the ESA HIPPARCOS Space Astrometry Mission", Esa Special Publication, 1200, Noordwijk, Netherlands: ESA Publications Division, Bibcode:1997ESASP1200.....E.
- ^ Cowley, A. P.; Bidelman, W. P. (February 1979), "MK spectral types for some F and G stars", Publications of the Astronomical Society of the Pacific, 91: 83–86, Bibcode:1979PASP...91...83C, doi:10.1086/130446.
- ^ 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.
