建五

建五（Rho1 Sagittarii，拉丁化）是人馬座的一顆恆星，是位於人馬座南側的一顆變星變星。它具有白色色調，肉眼可見，視星等在3.93左右變動。根據視差，這顆恆星距離太陽系大約127光年，並以+1.2公里/秒的徑向速度遠離太陽系。它位於黃道附近，因此可以被月球掩蔽。此外，太陽系的行星如水星與金星等也可能遮掩它，但這現象非常罕見。下一次被行星遮掩將發生在2046年2月23日，人馬座ρ¹被金星遮掩。 這個天體的恆星分類為A9IV，匹配遠離主序帶演化成為次巨星。這是一個低振幅的盾牌座δ型變星，範圍從3.94到3.90星等，週期為0.05天。這顆恆星的年齡為8億9300萬年，並且以68公里/秒的投影旋轉速度旋轉。它的質量是1.9倍太陽質量，和半徑3.3倍太陽半徑。這顆恆星來自光球輻射的光度是太陽光度的31倍，表面的有效溫度為7,469K。 Van Leeuwen, F. Validation of the new Hipparcos reduction. Astronomy and Astrophysics. 2007, 474 (2): 653–664. Bibcode:2007A&A...474..653V. S2CID 18759600. arXiv:0708.1752 . doi:10.1051/0004-6361:20078357.  Vizier catalog entry （页面存档备份，存于互联网档案馆） Ducati, J. R. VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system. CDS/ADC Collection of Electronic Catalogues. 2002, 2237. Bibcode:2002yCat.2237....0D.  Gray, R. O.; Corbally, C. J.; Garrison, R. F.; McFadden, M. T.; Bubar, E. J.; McGahee, C. E.; O'Donoghue, A. A.; Knox, E. R. Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc--The Southern Sample. The Astronomical Journal. 2006, 132: 161–170. Bibcode:2006AJ....132..161G. S2CID 119476992. arXiv:astro-ph/0603770 . doi:10.1086/504637.  Samus, N. N.; Durlevich, O. V.; et al. VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013). VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 2009, 1. Bibcode:2009yCat....102025S.  Wilson, R. E. General Catalogue of Stellar Radial Velocities. Carnegie Institution for Science. 1953. Bibcode:1953GCRV..C......0W. LCCN 54001336.  Anderson, E.; Francis, Ch. XHIP: An extended hipparcos compilation. Astronomy Letters. 2012, 38 (5): 331. Bibcode:2012AstL...38..331A. S2CID 119257644. arXiv:1108.4971 . doi:10.1134/S1063773712050015.  Vizier catalog entry （页面存档备份，存于互联网档案馆） Allende Prieto, C.; Lambert, D. L. Fundamental parameters of nearby stars from the comparison with evolutionary calculations: Masses, radii and effective temperatures. Astronomy and Astrophysics. 1999, 352: 555–562. Bibcode:1999A&A...352..555A. arXiv:astro-ph/9911002 .  Vizier catalog entry （页面存档备份，存于互联网档案馆） Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne, J. H. J.; et al. Gaia Data Release 2. Summary of the contents and survey properties. Astronomy & Astrophysics. 2018. Bibcode:2018A&A...616A...1G. arXiv:1804.09365 . doi:10.1051/0004-6361/201833051.  VizieR中此天体在盖亚望远镜第二批数据发布的记录 David, Trevor J.; Hillenbrand, Lynne A. 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. 2015, 804 (2): 146. Bibcode:2015ApJ...804..146D. S2CID 33401607. arXiv:1501.03154 . doi:10.1088/0004-637X/804/2/146.  Vizier catalog entry （页面存档备份，存于互联网档案馆） Gontcharov, G. A. Dependence of kinematics on the age of stars in the solar neighborhood. Astronomy Letters. 2012, 38 (12): 771–782. Bibcode:2012AstL...38..771G. S2CID 118345778. arXiv:1606.08814 . doi:10.1134/S1063773712120031.  Vizier catalog entry （页面存档备份，存于互联网档案馆） Hoffleit, D.; Warren, W. H. Bright Star Catalogue. VizieR On-line Data Catalog: V/50. Originally Published in: 1964BS....C......0H 5th Revised. 1995, 5050. Bibcode:1995yCat.5050....0H.  rho01 Sgr. SIMBAD. 斯特拉斯堡天文資料中心.  Eggleton, P. P.; Tokovinin, A. A. A catalogue of multiplicity among bright stellar systems. Monthly Notices of the Royal Astronomical Society. September 2008, 389 (2): 869–879. Bibcode:2008MNRAS.389..869E. S2CID 14878976. arXiv:0806.2878 . doi:10.1111/j.1365-2966.2008.13596.x.  Edwards, D. A.; Evans, D. S.; Fekel, F. C.; Smith, B. W. Photoelectric observations of lunar occultations. XI.. Astronomical Journal. April 1980, 85: 478–489. Bibcode:1980AJ.....85..478E. doi:10.1086/112700.