Star in the constellation Coma Berenices
7 Comae Berenices is a single[ 6] star located 249[ 1] light years away in the northern constellation of Coma Berenices . It is a dim star but visible to the naked eye near the Coma Star Cluster with an apparent visual magnitude of 4.93.[ 2] The star is moving closer to the Earth with a heliocentric radial velocity of −28 km/s,[ 4] and is predicted to come as close as 83 light-years in 2.4 million years.[ 2]
This is an evolved giant star with a stellar classification of G8 III–IIIb.[ 3] At the age of 730 million years it is a red clump giant, which indicates it is on the horizontal branch and is generating energy via helium fusion at its core .[ 7] The star has 2.4 times the mass of the Sun and has expanded to 10 times the Sun's radius . It is radiating about 63 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 5,023 K.[ 4]
References
^ a b c d e f van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics , 474 (2): 653– 664, arXiv :0708.1752 , Bibcode :2007A&A...474..653V , doi :10.1051/0004-6361:20078357 , S2CID 18759600 .
^ 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 Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series , 71 : 245, Bibcode :1989ApJS...71..245K , doi :10.1086/191373 .
^ a b c d Jofré, E.; et al. (2015), "Stellar parameters and chemical abundances of 223 evolved stars with and without planets", Astronomy & Astrophysics , 574 : A50, arXiv :1410.6422 , Bibcode :2015A&A...574A..50J , doi :10.1051/0004-6361/201424474 , S2CID 53666931 .
^ "7 Com" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved December 30, 2018 .
^ 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 .
^ Mishenina, T. V.; et al. (September 2006), "Elemental abundances in the atmosphere of clump giants", Astronomy and Astrophysics , 456 (3): 1109– 1120, arXiv :astro-ph/0605615 , Bibcode :2006A&A...456.1109M , doi :10.1051/0004-6361:20065141 , S2CID 18764566 .