Binary star in the constellation Ursa Major
Upsilon Ursae Majoris ,Latinized fromυ Ursae Majoris , is abinary star [ 12] northern circumpolar constellation ofUrsa Major . It is visible to the naked eye with anapparent visual magnitude of +3.79.[ 4] parallax shift of 13.24 mas ,[ 1] light-years from theSun .
Alight curve for Upsilon Ursae Majoris, plotted fromTESS [ 13] The primary member of the system, component A, is anF-type subgiant star. It is aDelta Scuti variable [ 8] amplitude of 0.050 magnitude.[ 14] [ 7] projected rotational velocity of 124.2 km/s[ 10] rotation period of 1.2 days.[ 8] [ 7] mass of the Sun and 2.79[ 8] Sun's radius . (De Rosa and colleagues give a mass estimate of 2.2[ 3] [ 9] solar luminosity from itsouter atmosphere at aneffective temperature of 7,211 K.[ 7]
The companion, component B, is a magnitude +11.0 star.[ 12] angular separation of 11.78 arcseconds along aposition angle of 295.4°. This corresponds to aprojected separation of 419.8 AU .[ 3] [ 3]
Withτ ,h ,φ ,θ ,e andf , it composed the Arabicasterism Sarīr Banāt al-Na'sh , the Throne of the daughters ofNa'sh , andAl-H aud , the Pond.[ 15] Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars ,Al-H aud were the title for seven stars :f asAlhaud I ,τ asAlhaud II ,e asAlhaud III ,h asAlhaud IV ,θ asAlhaud V , this star (υ) asAlhaud VI andφ asAlhaud VII .[ 16]
InChinese ,文昌 Wén Chāng Administrative Center φ Ursae Majoris ,θ Ursae Majoris ,15 Ursae Majoris and18 Ursae Majoris . Consequently, theChinese name for υ Ursae Majoris itself is文昌一 Wén Chāng yī the first Star of Administrative Center .).[ 17]
^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 Samus, N. N.; Durlevich, O. V.; et al. (2009), "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007–2013)",VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S ,1 ,Bibcode :2009yCat....102025S . ^a b c d e f De Rosa, R. J.; et al. (2013), "The VAST Survey – III. The multiplicity of A-type stars within 75 pc",Monthly Notices of the Royal Astronomical Society ,437 (2): 1216,arXiv :1311.7141 Bibcode :2014MNRAS.437.1216D ,doi :10.1093/mnras/stt1932 S2CID 88503488 . ^a b c Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)",Catalogue of Eggen's UBV Data ,SIMBAD ,Bibcode :1986EgUBV........0M . ^ 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. ^ Ammler-von Eiff, Matthias; Reiners, Ansgar (June 2012), "New measurements of rotation and differential rotation in A-F stars: are there two populations of differentially rotating stars?",Astronomy & Astrophysics ,542 : A116,arXiv :1204.2459 Bibcode :2012A&A...542A.116A ,doi :10.1051/0004-6361/201118724 ,S2CID 53666672 . ^a b c d e f g David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets",The Astrophysical Journal ,804 (2): 146,arXiv :1501.03154 Bibcode :2015ApJ...804..146D ,doi :10.1088/0004-637X/804/2/146 ,S2CID 33401607 . ^a b c d e Korzennik, S. G.; et al. (April 1995), "Nightly variations of nonradial oscillations in the Delta Scuti star upsilon Ursae Majoris",Astrophysical Journal, Part 2 ,443 (1):L25 – L28 ,Bibcode :1995ApJ...443L..25K ,doi :10.1086/187827 . ^a b Balona, L. A.; Dziembowski, W. A. (October 1999), "Excitation and visibility of high-degree modes in stars",Monthly Notices of the Royal Astronomical Society 309 (1):221– 232,Bibcode :1999MNRAS.309..221B ,doi :10.1046/j.1365-8711.1999.02821.x ^a b Schröder, C.; Reiners, Ansgar; Schmitt, Jürgen H. M. M. (January 2009),"Ca II HK emission in rapidly rotating stars. Evidence for an onset of the solar-type dynamo" (PDF) ,Astronomy and Astrophysics ,493 (3):1099– 1107,Bibcode :2009A&A...493.1099S ,doi :10.1051/0004-6361:200810377 [permanent dead link ^a b "ups UMa" ,SIMBAD Centre de données astronomiques de Strasbourg , retrieved2017-02-22 .^a b 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 . ^ MAST: Barbara A. Mikulski Archive for Space Telescopes , retrieved8 December 2021 .^ Rodríguez, E.; et al. (June 2000), "A revised catalogue of delta Sct stars",Astronomy and Astrophysics Supplement ,144 (3):469– 474,Bibcode :2000A&AS..144..469R ,doi :10.1051/aas:2000221 hdl :10261/226673 ^ Allen, Richard Hinckley (1899),Star-Names and Their Meanings , New York: G. E. Stechert, p. 442.^ Rhoads, Jack W. (November 15, 1971),Technical Memorandum 33-507-A Reduced Star Catalog Containing 537 Named Stars (PDF) , Jet Propulsion Laboratory, California Institute of Technology. ^ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 6 月 16 日 Archived 2012-02-04 at theWayback Machine
