52 Hydrae
Star in the constellation Hydra
52 Hydrae is a triple star system [ 7] in the constellation Hydra . It has the Bayer designation l Hydrae ; 52 Hydrae is the Flamsteed designation .[ 6] This system is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude of 4.97.[ 2] It is a probable (80% chance) member of the Sco OB2 moving group of stars,[ 8] and is moving away from the Earth with a heliocentric radial velocity of 5 km/s.[ 2]
The primary component is a binary system[ 7] consisting of two nearly equal components with an orbital period of around 15 years[ 9] and an angular separation of 0.1″ .[ 7] It shows a combined stellar classification of B7/8V,[ 5] which matches a B-type main-sequence star . The third component is a magnitude 10.0 star at a separation of 4.2″[ 7] with a mass similar to the Sun. It is orbiting the inner pair with a period of around 3,900 years.[ 9]
References
^ a b c d e 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 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 .
^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog" , The Astronomical Journal , 122 (6): 3466, Bibcode :2001AJ....122.3466M , doi :10.1086/323920 , retrieved 2015-07-22 .
^ a b c d e Zorec, J.; Royer, F. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics , 537 : A120, arXiv :1201.2052 , Bibcode :2012A&A...537A.120Z , doi :10.1051/0004-6361/201117691 , S2CID 55586789 .
^ a b Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars , vol. 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode :1982mcts.book.....H .
^ a b "l Hya" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved May 5, 2019 .
^ a b c d 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 .
^ Rizzuto, Aaron; et al. (October 2011), "Multidimensional Bayesian membership analysis of the Sco OB2 moving group", Monthly Notices of the Royal Astronomical Society , 416 (4): 3108–3117, arXiv :1106.2857 , Bibcode :2011MNRAS.416.3108R , doi :10.1111/j.1365-2966.2011.19256.x , S2CID 54510608 .
^ a b Tokovinin, A. (September 2008), "Comparative statistics and origin of triple and quadruple stars", Monthly Notices of the Royal Astronomical Society , 389 (2): 925–938, arXiv :0806.3263 , Bibcode :2008MNRAS.389..925T , doi :10.1111/j.1365-2966.2008.13613.x , S2CID 16452670 .