Binary star in the constellation Andromeda
φ Andromedae in optical light Phi Andromedae (φ Andromedae, φ And) is theBayer designation for abinary star [ 3] constellation ofAndromeda . This system has a combinedapparent visual magnitude of 4.25[ 2] visible to the naked eye . Based uponparallax measurements made during theHipparcos mission, this star system is located at a distance of about 720light-years (220parsecs ) from Earth.[ 1] χ And it forms the Chineseasterism 軍南門 (Keun Nan Mun ,Mandarin jūnnánmén) , "the South Gate of the Camp".[ 12] [ 13]
The 4.46[ 3] Be star with astellar classification of B7 Ve, indicating that it is aB-type main sequence star that shows prominentemission lines of hydrogen in its spectrum. These emission lines come from a flatteneddecretion disk of hot gas that is orbiting the host star.[ 4] projected rotational velocity of 75 km/s.[ 9] [ 4]
The 6.06 magnitude companion star is aB-type main sequence star with a classification of B9 V. On average the two stars are separated by about 0.6 arcseconds and have an orbital period of roughly 554 years. Based upon their orbital elements, the system has a combined mass of around6.5 ± 2.8 [ 7]
^a b c d e f van Leeuwen, F. (November 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 Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars",Communications of the Lunar and Planetary Laboratory ,4 (99): 99,Bibcode :1966CoLPL...4...99J . ^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 . ^a b c Silaj, J.; et al. (March 2010), "A Systematic Study of Hα Profiles of Be Stars",The Astrophysical Journal Supplement ,187 (1):228– 250,Bibcode :2010ApJS..187..228S ,doi :10.1088/0067-0049/187/1/228 S2CID 122679154 . ^ Wilson, Ralph Elmer (1953), "General catalogue of stellar radial velocities",Carnegie Institute Washington D.C. Publication , Carnegie Institution of Washington,Bibcode :1953GCRV..C......0W ^a b 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 Muterspaugh, Matthew W.; et al. (December 2010), "The Phases Differential Astrometry Data Archive. II. Updated Binary Star Orbits and a Long Period Eclipsing Binary",The Astronomical Journal ,140 (6):1623– 1630,arXiv :1010.4043 Bibcode :2010AJ....140.1623M ,doi :10.1088/0004-6256/140/6/1623 ,S2CID 6030289 . ^a b Soubiran, Caroline; et al. (2016), "The PASTEL catalogue: 2016 version",Astronomy & Astrophysics ,591 : A118,arXiv :1605.07384 Bibcode :2016A&A...591A.118S ,doi :10.1051/0004-6361/201628497 ,S2CID 119258214 . ^a b Abt, Helmut A.; Levato, Hugo; Grosso, Monica (July 2002), "Rotational Velocities of B Stars",The Astrophysical Journal ,573 (1):359– 365,Bibcode :2002ApJ...573..359A ,doi :10.1086/340590 ^ 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 . ^ "* phi And" .SIMBAD Centre de données astronomiques de Strasbourg . Retrieved2012-06-25 .^ Allen, R. H. (1899),Star-names and Their Meanings , New York: G. E. Stechart, p. 39.^ In Chinese literature, φ Andromedae is stand alone in the asterism and χ Andromeda is member ofTien Ta Tseang (Heaven's Great General) asterism, see(in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 9 日 Archived 2011-05-22 at theWayback Machine and(in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 10 日 Archived 2011-07-16 at theWayback Machine
