Upsilon2 Centauri
Binary star system in the constellation Centaurus
Upsilon2 Centauri (υ2 Centauri) is a binary star [ 6] system in the southern constellation Centaurus . It is visible to the naked eye with an apparent visual magnitude of +4.33.[ 2] Based upon an annual parallax shift of just 2.57 mas as seen from Earth,[ 1] this star is located roughly 1,300 light years from the Sun . Relative to its neighbors, the system has a peculiar velocity of 39.2+8.8 −15.2 km/s and it may form a runaway star system.[ 9]
This is a single-lined spectroscopic binary star system with an orbital period of 207.357 days and an eccentricity of 0.55.[ 6] The primary component has the spectrum of an evolved F-type giant /bright giant hybrid with a stellar classification of F7 II/III.[ 3] It is around 46[ 9] million years old with 6.9 times the mass of the Sun . The star is radiating 3,919 times the Sun's luminosity from its photosphere at an effective temperature of 6,495 K.[ 7]
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 Fernie, J. D. (1983), "New UBVRI photometry for 900 supergiants", Astrophysical Journal Supplement Series , 52 : 7, Bibcode :1983ApJS...52....7F , doi :10.1086/190856 .
^ a b Houk, N. (1987), "Michigan Catalogue of two dimensional spectral types for the HD stars", Michigan Spectral Survey , 2 , Bibcode :1978mcts.book.....H .
^ a b Eggen, O. J. (July 1985), "Cepheids and nonvariable supergiants", Astronomical Journal , 90 : 1260–1277, Bibcode :1985AJ.....90.1260E , doi :10.1086/113834 .
^ de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics , 546 : 14, arXiv :1208.3048 , Bibcode :2012A&A...546A..61D , doi :10.1051/0004-6361/201219219 , S2CID 59451347 , A61.
^ a b c Pourbaix, D.; et al. (2004), "SB9: The Ninth Catalogue of Spectroscopic Binary Orbits", Astronomy & Astrophysics , 424 : 727–732, arXiv :astro-ph/0406573 , Bibcode :2004A&A...424..727P , doi :10.1051/0004-6361:20041213 , S2CID 119387088 .
^ a b c d Hohle, M. M.; et al. (April 2010), "Masses and luminosities of O- and B-type stars and red supergiants", Astronomische Nachrichten , 331 (4): 349, arXiv :1003.2335 , Bibcode :2010AN....331..349H , doi :10.1002/asna.200911355 , S2CID 111387483 .
^ a b Mallik, Sushma V.; et al. (October 2003), "Lithium and rotation in F and G dwarfs and subgiants", Astronomy and Astrophysics , 409 : 251–261, Bibcode :2003A&A...409..251M , doi :10.1051/0004-6361:20031084 .
^ a b c Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society , 410 (1): 190–200, arXiv :1007.4883 , Bibcode :2011MNRAS.410..190T , doi :10.1111/j.1365-2966.2010.17434.x , S2CID 118629873 .
^ "ups02 Cen" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2017-08-29 .