南十字座θ2拉丁文θ2 Crucis,是在南十字座的一對光譜聯星。它們的完整軌道週期是3.4280天,軌道離心率非常低,趨近於0.0[11]。南十字座θ2太陽的距離約750光年[2]

南十字座θ2
觀測資料
曆元 J2000
星座 南十字座
星官
赤經 12h 04m 19.21504s[1]
赤緯 −63° 09′ 56.5537″[2]
視星等(V) 4.718[3]
特性
光谱分类B3 V[4]
U−B 色指数−0.61[5]
B−V 色指数−0.08[5]
变星类型仙王座β
天体测定
徑向速度 (Rv)+16.3[6] km/s
自行 (μ) 赤经:−17.63[2] mas/yr
赤纬:−0.01[2] mas/yr
视差 (π)3.82 ± 0.32[2] mas
距离850 ± 70 ly
(260 ± 20 pc)
绝对星等 (MV)−2.35[7]
軌道[8]
繞行週期 (P)3.428 d
偏心率 (e)0.00
近心点 曆元 (T)2419604.367 JD
半振幅 (K1)
(primary)
51.3 km/s
詳細資料
亮度809[9] L
溫度9,598[9] K
自轉速度 (v sin i)23[10] km/s
其他命名
θ2 Cru, CD−62° 610, HD 104841, HIP 58867, HR 4603, SAO 251717.[3]
參考資料庫
SIMBAD资料

該系統組合的平均視星等為+4.72m。由於其中有一顆是仙王座β型變星,星等在+4.70m和+4.74m之間稍有變化,使得星等不能固定,這個變化的週期是0.0889天[12]。這個系統被歸類為藍白的B型主序星恆星光譜為B3V[4]

參考資料

编辑
  1. ^ van Leeuwen, F., Validation of the new Hipparcos reduction, Astronomy and Astrophysics, 2007, 474 (2): 653–664, Bibcode:2007A&A...474..653V, arXiv:0708.1752 , doi:10.1051/0004-6361:20078357. 
  2. ^ 2.0 2.1 2.2 2.3 2.4 Perryman, M. A. C.; et al. The HIPPARCOS Catalogue. Astronomy & Astrophysics. April 1997, 323: L49–L52. Bibcode:1997A&A...323L..49P. 
  3. ^ 3.0 3.1 V* tet02 Cru. SIMBAD. 斯特拉斯堡天文資料中心. [2010-05-19]. 
  4. ^ 4.0 4.1 Houk, N.; Cowley, A. P., University of Michigan Catalogue of two-dimensional spectral types for the HD stars 1, 1975, Bibcode:1975mcts.book.....H. 
  5. ^ 5.0 5.1 Johnson, H. L.; Iriarte, B.; Mitchell, R. I.; Wisniewskj, W. Z. UBVRIJKL photometry of the bright stars. Communications of the Lunar and Planetary Laboratory. 1966, 4 (99). Bibcode:1966CoLPL...4...99J. 
  6. ^ Wilson, Ralph Elmer. General Catalogue of Stellar Radial Velocities. Washington: Carnegie Institution of Washington. 1953. Bibcode:1953GCRV..C......0W. 
  7. ^ Anderson, E.; Francis, Ch., XHIP: An extended hipparcos compilation, Astronomy Letters, 2012, 38 (5): 331, Bibcode:2012AstL...38..331A, arXiv:1108.4971 , doi:10.1134/S1063773712050015. 
  8. ^ Pourbaix, D.; Tokovinin, A. A.; Batten, A. H.; Fekel, F. C.; Hartkopf, W. I.; et al, SB9: The ninth catalogue of spectroscopic binary orbits, Astronomy & Astrophysics, 2004, 424 (2): 727, Bibcode:2004A&A...424..727P, arXiv:astro-ph/0406573 , doi:10.1051/0004-6361:20041213. 
  9. ^ 9.0 9.1 McDonald, I.; et al, Fundamental Parameters and Infrared Excesses of Hipparcos Stars, Monthly Notices of the Royal Astronomical Society, 2012, 427 (1): 343–57, Bibcode:2012MNRAS.427..343M, arXiv:1208.2037 , doi:10.1111/j.1365-2966.2012.21873.x. 
  10. ^ Bernacca, P. L.; Perinotto, M. A catalogue of stellar rotational velocities. Contributi Osservatorio Astronomico di Padova in Asiago. 1970, 239 (1). Bibcode:1970CoAsi.239....1B. 
  11. ^ Batten, A. H. Sixth catalogue of the orbital elements of spectroscopic binary systems. Publications of the Dominion Astrophysical Observatory, Victoria. 1967, 13: 154–155. Bibcode:1967PDAO...13..119B. 
  12. ^ Samus, N. N.; Durlevich, O. V.; et al. General Catalogue of Variable Stars. VizieR. January 2009 [2010-05-19]. (原始内容存档于2013-04-23).  Note: query for GCVS "tet 2 Cru".