HR 6594
Binary star system in the constellation of Hercules
HR 6594 is the Bright Star Catalogue designation for a binary star [12] system in the northern constellation of Hercules . It is faintly visible to the naked eye with an apparent visual magnitude of 5.54;[2] according to the Bortle scale , it is sufficiently bright to be visible from dark suburban skies. The distance to this system, as determined using parallax measurements,[1] is about 114 light years . It is drifting closer with a heliocentric radial velocity of −43.7 km/s,[6] and is predicted to come as near as 47 light-years in 686,000 years.[2] On the celestial sphere it is located near the star Alpha Ophiuchi ; their projected separation is just 3 light years, although their actual separation is much greater.[13]
The primary is an F-type main sequence star with a stellar classification of F4 Vw, where the w indicates relatively weak metallic features in the ultraviolet spectrum.[4] This star has 134% of the Sun's mass ,[8] but only 97% of the solar radius .[9] It is spinning with a projected rotational velocity of 31.7 km/s,[3] and is around 1.2 billion years old.[8] The effective temperature of the outer atmosphere is 6,615 K,[3] giving it the yellow-white hue of an F-type star .[14] The abundance of elements other than hydrogen or helium, what astronomers term the metallicity , is similar to that in the Sun.[10]
It has a magnitude 9.38 companion star orbiting with a 144-year period , a semimajor axis spanning 1.04 arcseconds , and an eccentricity of 0.42.[12] There is a third, visual companion of magnitude 14.46 at an angular separation of 154.70 arcseconds along a position angle of 271°, as of 2001.[15]
References
^ a b c d e Brown, A. G. A. ; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties" . Astronomy & Astrophysics . 649 : A1. arXiv :2012.01533 . Bibcode :2021A&A...649A...1G . doi :10.1051/0004-6361/202039657 . S2CID 227254300 . (Erratum: doi :10.1051/0004-6361/202039657e ) . Gaia EDR3 record for this source at VizieR .
^ a b c d e 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 e f [permanent dead link ]
^ a b Barry, Don C. (1970), "Spectral Classification of A and F Stars", Astrophysical Journal Supplement , 19 : 281, Bibcode :1970ApJS...19..281B , doi :10.1086/190209 .
^ Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data , SIMBAD , Bibcode :1986EgUBV........0M .
^ a b Wilson, R. E. (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication , Carnegie Institute of Washington D.C. , Bibcode :1953GCRV..C......0W .
^ Boesgaard, A. M.; Tripicco, M. J. (April 15, 1986), "Lithium in early F dwarfs", Astrophysical Journal, Part 1 , 303 : 724–739, Bibcode :1986ApJ...303..724B , doi :10.1086/164120 .
^ a b c d 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 .
^ a b Pasinetti-Fracassini, L. E.; et al. (February 2001), "Catalogue of Stellar Diameters (CADARS)", Astronomy and Astrophysics , 367 : 521–524, arXiv :astro-ph/0012289 , Bibcode :2001A&A...367..521P , doi :10.1051/0004-6361:20000451 , S2CID 425754 .
^ a b 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 & Astrophysics , 530 (A138): 21, arXiv :1103.4651 , Bibcode :2011A&A...530A.138C , doi :10.1051/0004-6361/201016276 , S2CID 56118016 .
^ "HR 6594" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2016-09-12 .
^ a b Malkov, O. Yu.; et al. (October 2012), "Dynamical masses of a selected sample of orbital binaries", Astronomy & Astrophysics , 546 : 5, Bibcode :2012A&A...546A..69M , doi :10.1051/0004-6361/201219774 , A69.
^ Redfield, Seth; et al. (June 2007), "Spitzer Limits on Dust Emission and Optical Gas Absorption Variability around Nearby Stars with Edge-on Circumstellar Disk Signatures", The Astrophysical Journal , 661 (2): 944–971, arXiv :astro-ph/0703089 , Bibcode :2007ApJ...661..944R , doi :10.1086/517516 , S2CID 42241365 .
^ "The Colour of Stars" , Australia Telescope, Outreach and Education , Commonwealth Scientific and Industrial Research Organisation , December 21, 2004, archived from the original on March 18, 2012, retrieved 2012-01-16 .
^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog" , The Astronomical Journal , 122 (6): 3466–3471, Bibcode :2001AJ....122.3466M , doi :10.1086/323920 , retrieved 2015-07-22 .