南十字座η

南十字座η (η Crucis)是在南十字座的一颗孤独恒星,它的视星等为可以用肉眼看见的4.14m[2]。依据恒星视差的测量[1],南十字座η与太阳相距64光年。大约在160万年前,这颗恒星最接近太阳时的距离大约是26光年 [10]

南十字座η
观测资料
历元 J2000.0ICRS
星座 南十字座
星官
赤经 12h 06m 52.89900s[1]
赤纬 −64° 36′ 49.4244″[1]
视星等(V) 4.14[2]
特性
光谱分类F2 V[3]
U−B 色指数+0.00[2]
B−V 色指数+0.35[2]
天体测定
径向速度 (Rv)+9.0[4] km/s
自行 (μ) 赤经:+33.88[1] mas/yr
赤纬:−37.02[1] mas/yr
视差 (π)50.62 ± 0.12[1] mas
距离64.4 ± 0.2 ly
(19.76 ± 0.05 pc)
绝对星等 (MV)2.67[5]
详细资料
半径1.3[6] R
表面重力 (log g)4.01[3]
亮度7[7] L
温度6,964[5] K
金属量 [Fe/H]−0.04[3] dex
自转速度 (v sin i)46.1±2.3[5] km/s
年龄2.53[8] Gyr
其他命名
η Cru, CD−63° 2145, GJ 9388, HD 105211, HIP 59072, HR 4616, SAO 251742.[9]
参考数据库
SIMBAD资料

这是一颗F型主序星光谱类型为F2V[3]。它的半径是太阳半径的130%[6],光度是太阳光度的7倍[7],来自外大气层有效温度是6964K[5]。使用史匹哲太空望远镜对该系统的观测显示,在波长为70微米的情况下,在统计学上有红外过量的现象,这表明存在着星周盘,而且盘中物质的温度低于70K[8]

南十字座η有一对光学伴星。伴星B的视星等为11.8等,在2010年的角距离是48.30角秒方位角300°。伴星C的视星等为12.16等,在2000年的角距离是25.50”,方位角194°[11]

参考资料

  1. ^ 1.0 1.1 1.2 1.3 1.4 1.5 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 ^ 2.0 2.1 2.2 2.3 Mermilliod, J.-C., Compilation of Eggen's UBV data, transformed to UBV (unpublished), SIMBAD, 1986, Bibcode:1986EgUBV........0M. 
  3. ^ 3.0 3.1 3.2 3.3 Gray, R. O.; et al, Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample, The Astronomical Journal, July 2006, 132 (1): 161–170, Bibcode:2006AJ....132..161G, arXiv:astro-ph/0603770 , doi:10.1086/504637. 
  4. ^ Wilson, R. E., General Catalogue of Stellar Radial Velocities, Carnegie Institute of Washington, D.C., 1953, Bibcode:1953GCRV..C......0W. 
  5. ^ 5.0 5.1 5.2 5.3 Ammler-von Eiff, M.; Reiners, A., New measurements of rotation and differential rotation in A-F stars: Are there two populations of differentially rotating stars?, Astronomy & Astrophysics, 2012, 542: A116, Bibcode:2012A&A...542A.116A, arXiv:1204.2459 , doi:10.1051/0004-6361/201118724. 
  6. ^ 6.0 6.1 Pasinetti Fracassini, L. E.; et al, Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics, Astronomy and Astrophysics, February 2001, 367 (2): 521–524, Bibcode:2001A&A...367..521P, arXiv:astro-ph/0012289 , doi:10.1051/0004-6361:20000451. 
  7. ^ 7.0 7.1 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. 
  8. ^ 8.0 8.1 Beichman, C. A.; et al, New Debris Disks around Nearby Main-Sequence Stars: Impact on the Direct Detection of Planets, The Astrophysical Journal, December 2006, 652 (2): 1674–1693, Bibcode:2006ApJ...652.1674B, arXiv:astro-ph/0611682 , doi:10.1086/508449. 
  9. ^ eta Cru. SIMBAD. 斯特拉斯堡天文资料中心. [2016-10-06]. 
  10. ^ Bailer-Jones, C. A. L., Close encounters of the stellar kind, Astronomy & Astrophysics, March 2015, 575: 13, Bibcode:2015A&A...575A..35B, arXiv:1412.3648 , doi:10.1051/0004-6361/201425221, A35. 
  11. ^ Mason, B. D.; et al, The Washington Visual Double Star Catalog, The Astronomical Journal, 2014, 122: 3466–3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920. 

外部链接

  • Kaler, James B., Eta Crucis, Stars (University of Illinois), [2016-10-08], (原始内容存档于2020-09-19).