Alpha Comae Berenices (α Comae Berenices, abbreviated Alpha Com, α Com) is a binary star in the constellation of Coma Berenices (Berenice's Hair), 17.8 parsecs (58 ly) away. It consists of two main sequence stars, each a little hotter and more luminous than the Sun.
Alpha Comae Berenices is said to represent the crown worn by Queen Berenice. The two components are designated Alpha Comae Berenices A (officially named Diadem/ˈdaɪədɛm/, the traditional name for the system)[14] and B.
The system bore the traditional names Diadem and Al Dafirah, the latter derived from the Arabic الضفيرة ađ̧-đ̧afīrah "the braid".[citation needed] In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN)[16] to catalogue and standardize proper names for stars. The WGSN decided to attribute proper names to individual stars rather than entire multiple systems.[17] It approved the name Diadem for the component Alpha Comae Berenices A on 1 February 2017 and it is now so included in the List of IAU-approved Star Names.[14]
In Chinese, 太微左垣 (Tài Wēi Zuǒ Yuán), meaning Left Wall of Supreme Palace Enclosure, refers to an asterism consisting of Alpha Comae Berenices, Eta Virginis, Gamma Virginis, Delta Virginis and Epsilon Virginis.[18] Consequently, the Chinese name for Alpha Comae Berenices itself is 太微左垣五 (Tài Wēi Zuǒ Yuán wǔ, English: the Fifth Star of Left Wall of Supreme Palace Enclosure.),[19] representing 東上將 (Dōngshǎngjiāng), meaning The First Eastern General.[20] 東上將 (Dōngshǎngjiāng), westernized into Shang Tseang, but that name was designated for "v Comae Berenices" by R.H. Allen and the meaning is "a Higher General".[21]
It is a binary star, with almost equal components of magnitudes 5.05 m and 5.08 m orbiting each other with a period of 25.87 years. The system, estimated to be 58 light-years distant, appears so nearly "edge-on" from the Earth that the two stars appear to move back-and-forth in a straight line with a maximum separation of only 0.7 arcsec. Eclipses are predicted to occur between the two components however they have not been successfully observed due to miscalculations of the time of eclipse.[8]
The mean separation between them is approximately 10 AU, about the distance between the Sun and Saturn.
The binary star has a visual companion, CCDM J13100+1732C, of apparent magnitude 10.2, located 89 arcseconds away along a position angle of 345°.[22]
Alpha Comae Berenicis forms an isosceles triangle with globular star clusters Messier 53 and NGC 5053. The apparent diameter of this triangle is a little more than one degree. The location of Alpha Comae Berenicis is westward (preceding) of both globular star clusters.
Referencesedit
^ abcdevan 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. Vizier catalog entry
^NSV 6116, database entry, New Catalogue of Suspected Variable Stars, the improved version, Sternberg Astronomical Institute, Moscow, Russia. Accessed on line September 3, 2008.
^Diadem 2008-05-11 at the Wayback Machine, Jim Kaler, Stars. Accessed on line September 3, 2008.
^ abHR 4968, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line September 3, 2008.
^ abcdNSV 6116 -- Variable Star, database entry, SIMBAD. Accessed on line September 3, 2008.
^Reiners, Ansgar (January 2006), "Rotation- and temperature-dependence of stellar latitudinal differential rotation", Astronomy and Astrophysics, 446 (1): 267–277, arXiv:astro-ph/0509399, Bibcode:2006A&A...446..267R, doi:10.1051/0004-6361:20053911, S2CID 8642707
^ abMuterspaugh, Matthew W.; et al. (2015). "Predicting the α Comae Berenices Time of Eclipse: How 3 Ambiguous Measurements out of 609 Caused a 26 Year Binary's Eclipse to be Missed". The Astronomical Journal. 150 (5). 140. arXiv:1501.05639. Bibcode:2015AJ....150..140M. doi:10.1088/0004-6256/150/5/140. S2CID 119282868.
^ abPavlovic, R.; Todorovic, N. (2005). "Orbits of Seven Edge-On Visual Double Stars". Serbian Astronomical Journal. 170 (170): 73–78. Bibcode:2005SerAJ.170...73P. doi:10.2298/SAJ0570073P.
^ abcTen Brummelaar, Theo; Mason, Brian D.; McAlister, Harold A.; Roberts, Lewis C.; Turner, Nils H.; Hartkopf, William I.; Bagnuolo, William G. (2000). "Binary Star Differential Photometry Using the Adaptive Optics System at Mount Wilson Observatory". The Astronomical Journal. 119 (5): 2403. Bibcode:2000AJ....119.2403T. doi:10.1086/301338.
^ abcSoubiran, Caroline; Le Campion, Jean-François; Brouillet, Nathalie; Chemin, Laurent (2016). "The PASTEL catalogue: 2016 version". Astronomy and Astrophysics. 591: A118. arXiv:1605.07384. Bibcode:2016A&A...591A.118S. doi:10.1051/0004-6361/201628497. S2CID 119258214.
^HD 114378 -- Star in double system, database entry, SIMBAD, accessed on line September 3, 2008.
^HD 114379 -- Star in double system, database entry, SIMBAD, accessed on line September 3, 2008.
^ ab"Naming Stars". IAU.org. Retrieved 16 December 2017.
^Hessman, F. V.; Dhillon, V. S.; Winget, D. E.; Schreiber, M. R.; Horne, K.; Marsh, T. R.; Guenther, E.; Schwope, A.; Heber, U. (2010). "On the naming convention used for multiple star systems and extrasolar planets". arXiv:1012.0707 [astro-ph.SR].
^"International Astronomical Union | IAU". www.iau.org. Retrieved 2017-03-31.
^"WG Triennial Report (2015-2018) - Star Names" (PDF). p. 5. Retrieved 2018-07-14.
^(in Chinese)中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN978-986-7332-25-7.
^(in Chinese) 香港太空館 - 研究資源 - 亮星中英對照表 2009-09-29 at the Wayback Machine, Hong Kong Space Museum. Accessed on line November 23, 2010.
^(in Chinese) English-Chinese Glossary of Chinese Star Regions, Asterisms and Star Name 2008-09-24 at the Wayback Machine, Hong Kong Space Museum. Accessed on line November 23, 2010.
^Richard Hinckley Allen: Star Names — Their Lore and Meaning: Coma Berenices
^Entry 13100+1732, discoverer code STF1728, components AB-C, The Washington Double Star Catalog 2008-04-13 at the Wayback Machine, United States Naval Observatory. Accessed on line September 3, 2008.
External linksedit
May 03, 2024
alpha, comae, berenices, comae, berenices, abbreviated, alpha, binary, star, constellation, coma, berenices, berenice, hair, parsecs, away, consists, main, sequence, stars, each, little, hotter, more, luminous, than, comae, berenicesα, comae, berenices, circle. Alpha Comae Berenices a Comae Berenices abbreviated Alpha Com a Com is a binary star in the constellation of Coma Berenices Berenice s Hair 17 8 parsecs 58 ly away It consists of two main sequence stars each a little hotter and more luminous than the Sun a Comae Berenicesa Comae Berenices circled in the constellation Coma Berenices Observation dataEpoch J2000 0 Equinox J2000 0 ICRS Constellation Coma Berenices Right ascension 13h 09m 59 285s 1 Declination 17 31 46 04 1 Apparent magnitude V 4 29 to 4 35 combined 2 A 4 85 B 5 53 3 Characteristics Spectral type A F5V B F5V binary star 4 U B color index 0 06 5 B V color index 0 45 5 V R color index 0 2 6 R I color index 0 2 6 AstrometryRadial velocity Rv 17 7 0 9 6 km sProper motion m RA 433 13 0 70 1 mas yr Dec 141 24 0 51 1 mas yrParallax p 56 10 0 89 mas 1 Distance58 1 0 9 ly 17 8 0 3 pc Absolute magnitude MV 3 82 7 Orbit 8 Period P 25 8696 0 008219 yrSemi major axis a 0 67144 0 00033 Eccentricity e 0 51060 0 00061Inclination i 90 0501 0 0062 Longitude of the node W 12 2272 0 0098 Periastron epoch T 57056 84 0 36Argument of periastron w secondary 100 563 0 026 DetailsAMass1 237 9 M Luminosity1 72 10 L Surface gravity log g 4 19 11 cgsTemperature6 365 11 KMetallicity Fe H 0 23 11 dexBMass1 087 9 M Luminosity1 75 10 L Temperature6 378 10 K Other designationsa Com Alpha Comae Berenices Alpha Com 42 Comae Berenices 42 Com STF 1728 ADS 8804 BD 18 2697 CCDM J13100 1732 GC 17833 Gliese 501 HIP 64241 IDS 13051 1803 AB LTT 13802 NLTT 33105 PPM 129630 SAO 100443 WDS 13100 1732 6 12 13 A HD 114378 HR 4968B HD 114379 HR 4969 Database referencesSIMBADdata Alpha Comae Berenices is said to represent the crown worn by Queen Berenice The two components are designated Alpha Comae Berenices A officially named Diadem ˈ d aɪ e d ɛ m the traditional name for the system 14 and B Contents 1 Nomenclature 2 Properties 3 References 4 External linksNomenclature edita Comae Berenices Latinised to Alpha Comae Berenices is the system s Bayer designation The designations of the two components as Alpha Comae Berenices A and B derive from the convention used by the Washington Multiplicity Catalog WMC for multiple star systems and adopted by the International Astronomical Union IAU 15 The system bore the traditional names Diadem and Al Dafirah the latter derived from the Arabic الضفيرة ađ đ afirah the braid citation needed In 2016 the International Astronomical Union organized a Working Group on Star Names WGSN 16 to catalogue and standardize proper names for stars The WGSN decided to attribute proper names to individual stars rather than entire multiple systems 17 It approved the name Diadem for the component Alpha Comae Berenices A on 1 February 2017 and it is now so included in the List of IAU approved Star Names 14 In Chinese 太微左垣 Tai Wei Zuǒ Yuan meaning Left Wall of Supreme Palace Enclosure refers to an asterism consisting of Alpha Comae Berenices Eta Virginis Gamma Virginis Delta Virginis and Epsilon Virginis 18 Consequently the Chinese name for Alpha Comae Berenices itself is 太微左垣五 Tai Wei Zuǒ Yuan wǔ English the Fifth Star of Left Wall of Supreme Palace Enclosure 19 representing 東上將 Dōngshǎngjiang meaning The First Eastern General 20 東上將 Dōngshǎngjiang westernized into Shang Tseang but that name was designated for v Comae Berenices by R H Allen and the meaning is a Higher General 21 Properties editAlthough Alpha Comae Berenices bears the title alpha at magnitude 4 32 it is actually fainter than Beta Comae Berenices It is a binary star with almost equal components of magnitudes 5 05 m and 5 08 m orbiting each other with a period of 25 87 years The system estimated to be 58 light years distant appears so nearly edge on from the Earth that the two stars appear to move back and forth in a straight line with a maximum separation of only 0 7 arcsec Eclipses are predicted to occur between the two components however they have not been successfully observed due to miscalculations of the time of eclipse 8 The mean separation between them is approximately 10 AU about the distance between the Sun and Saturn The binary star has a visual companion CCDM J13100 1732C of apparent magnitude 10 2 located 89 arcseconds away along a position angle of 345 22 Alpha Comae Berenicis forms an isosceles triangle with globular star clusters Messier 53 and NGC 5053 The apparent diameter of this triangle is a little more than one degree The location of Alpha Comae Berenicis is westward preceding of both globular star clusters References edit 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 amp A 474 653V doi 10 1051 0004 6361 20078357 S2CID 18759600 Vizier catalog entry NSV 6116 database entry New Catalogue of Suspected Variable Stars the improved version Sternberg Astronomical Institute Moscow Russia Accessed on line September 3 2008 Entry 13100 1732 Sixth Catalog of Orbits of Visual Binary Stars Archived 2005 04 24 at the Wayback Machine United States Naval Observatory Accessed on line September 3 2008 Diadem Archived 2008 05 11 at the Wayback Machine Jim Kaler Stars Accessed on line September 3 2008 a b HR 4968 database entry The Bright Star Catalogue 5th Revised Ed Preliminary Version D Hoffleit and W H Warren Jr CDS ID V 50 Accessed on line September 3 2008 a b c d NSV 6116 Variable Star database entry SIMBAD Accessed on line September 3 2008 Reiners Ansgar January 2006 Rotation and temperature dependence of stellar latitudinal differential rotation Astronomy and Astrophysics 446 1 267 277 arXiv astro ph 0509399 Bibcode 2006A amp A 446 267R doi 10 1051 0004 6361 20053911 S2CID 8642707 a b Muterspaugh Matthew W et al 2015 Predicting the a Comae Berenices Time of Eclipse How 3 Ambiguous Measurements out of 609 Caused a 26 Year Binary s Eclipse to be Missed The Astronomical Journal 150 5 140 arXiv 1501 05639 Bibcode 2015AJ 150 140M doi 10 1088 0004 6256 150 5 140 S2CID 119282868 a b Pavlovic R Todorovic N 2005 Orbits of Seven Edge On Visual Double Stars Serbian Astronomical Journal 170 170 73 78 Bibcode 2005SerAJ 170 73P doi 10 2298 SAJ0570073P a b c Ten Brummelaar Theo Mason Brian D McAlister Harold A Roberts Lewis C Turner Nils H Hartkopf William I Bagnuolo William G 2000 Binary Star Differential Photometry Using the Adaptive Optics System at Mount Wilson Observatory The Astronomical Journal 119 5 2403 Bibcode 2000AJ 119 2403T doi 10 1086 301338 a b c Soubiran Caroline Le Campion Jean Francois Brouillet Nathalie Chemin Laurent 2016 The PASTEL catalogue 2016 version Astronomy and Astrophysics 591 A118 arXiv 1605 07384 Bibcode 2016A amp A 591A 118S doi 10 1051 0004 6361 201628497 S2CID 119258214 HD 114378 Star in double system database entry SIMBAD accessed on line September 3 2008 HD 114379 Star in double system database entry SIMBAD accessed on line September 3 2008 a b Naming Stars IAU org Retrieved 16 December 2017 Hessman F V Dhillon V S Winget D E Schreiber M R Horne K Marsh T R Guenther E Schwope A Heber U 2010 On the naming convention used for multiple star systems and extrasolar planets arXiv 1012 0707 astro ph SR International Astronomical Union IAU www iau org Retrieved 2017 03 31 WG Triennial Report 2015 2018 Star Names PDF p 5 Retrieved 2018 07 14 in Chinese 中國星座神話 written by 陳久金 Published by 台灣書房出版有限公司 2005 ISBN 978 986 7332 25 7 in Chinese 香港太空館 研究資源 亮星中英對照表 Archived 2009 09 29 at the Wayback Machine Hong Kong Space Museum Accessed on line November 23 2010 in Chinese English Chinese Glossary of Chinese Star Regions Asterisms and Star Name Archived 2008 09 24 at the Wayback Machine Hong Kong Space Museum Accessed on line November 23 2010 Richard Hinckley Allen Star Names Their Lore and Meaning Coma Berenices Entry 13100 1732 discoverer code STF1728 components AB C The Washington Double Star Catalog Archived 2008 04 13 at the Wayback Machine United States Naval Observatory Accessed on line September 3 2008 External links edit Retrieved from https en wikipedia org w index php title Alpha Comae Berenices amp oldid 1079517410, wikipedia, wiki, book, books, library,
