郎位一(英语:Gamma Comae Berenices),英文名称来自拉丁文的γ Comae Berenices,是在星座后发座的一颗单独[10]的橙色恒星。它的光度以肉眼隐约可见,视星等为4.36等[2]。基于从地球上观察每年19.50mas视差,估计它与太阳的距离大约为167光年。这颗恒星正以+3公里/秒的径向速度远离太阳[5]

郎位一(γ Comae Berenices
观测资料
历元 J2000.0
星座 后发座
星官 郎位太微垣
赤经 12h 26m 56.27207s[1]
赤纬 +28° 16′ 06.3211″[1]
视星等(V) 4.36[2]
特性
光谱分类K1 III Fe0.5[3]
U−B 色指数+1.16[2]
B−V 色指数+1.13[2]
R−I 色指数+0.51[4]
天体测定
径向速度 (Rv)+3.38±0.11[5] km/s
自行 (μ) 赤经:−83.990 ± 0.418[6] mas/yr
赤纬:−82.216 ± 0.345[6] mas/yr
视差 (π)19.2552 ± 0.2371[6] mas
距离169 ± 2 ly
(51.9 ± 0.6 pc)
绝对星等 (MV)0.76[7]
详细资料 [8]
质量1.65±0.18 M
半径11.76±0.14 R
表面重力 (log g)2.53±0.05
亮度58.2±1.1 L
温度4,652±18 K
金属量 [Fe/H]0.16±0.10 dex
自转速度 (v sin i)≤ 17[4] km/s
年龄2.72±0.78 Gyr
其他命名
γ Com、​15 Comae Berenices、​BD+29° 2288、​FK5 2999、​GC 16964、​HD 108381、​HIP 60742、​HR 4737、​SAO 82313、​PPM 101903[9]
参考资料库
SIMBAD资料

这是一颗演化中的K型 巨星恒星分类K1 III Fe0.5[3]。后缀符号Fe表示这颗恒星在其光谱中显示出过多的铁。它最有可能(91%的几率)在水平分支上,年龄为27亿年。如果这是正确的,那么估计它的质量是太阳质量的1.65倍,并且半径已经膨胀到太阳半径的近12倍。这颗恒星表面的有效温度约为4,652 K,从其扩大的光球辐射出58倍于太阳的光度[8]。郎位一的位置在后发星团的区域内,但是它实际上可能不是这个星团的成员[11]

参考资料

  1. ^ 1.0 1.1 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. 
  2. ^ 2.0 2.1 2.2 2.3 Haupt, H. F.; Schroll, A., Photoelektrische Photometrie von Shell-Sternen, Astronomy and Astrophysics Supplement Series, 1974, 15: 311, Bibcode:1974A&AS...15..311H. 
  3. ^ 3.0 3.1 Keenan, Philip C; McNeil, Raymond C, The Perkins catalog of revised MK types for the cooler stars, Astrophysical Journal Supplement Series, 1989, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373. 
  4. ^ 4.0 4.1 Hoffleit, D.; Warren, Jr., W. H., HR 4737 database entry, The Bright Star Catalogue 5th Revised (Preliminary Version), [2024-04-16], (原始内容存档于2020-10-03) 
  5. ^ 5.0 5.1 Famaey, B.; et al, Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters, Astronomy and Astrophysics, January 2005, 430 (1): 165–186, Bibcode:2005A&A...430..165F, S2CID 17804304, arXiv:astro-ph/0409579 , doi:10.1051/0004-6361:20041272 
  6. ^ 6.0 6.1 6.2 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
  7. ^ Hekker, S.; et al, Precise radial velocities of giant stars. I. Stable stars, Astronomy and Astrophysics, August 2006, 454 (3): 943–949, Bibcode:2006A&A...454..943H, S2CID 119529768, arXiv:astro-ph/0604502 , doi:10.1051/0004-6361:20064946 
  8. ^ 8.0 8.1 Reffert, Sabine; et al, Precise radial velocities of giant stars. VII. Occurrence rate of giant extrasolar planets as a function of mass and metallicity, Astronomy and Astrophysics, 2015, 574A (2): 116–129, Bibcode:2015A&A...574A.116R, S2CID 59334290, arXiv:1412.4634 , doi:10.1051/0004-6361/201322360. 
  9. ^ * gam Com -- Star in Cluster, database entry, SIMBAD. Accessed on line October 12, 2010.
  10. ^ 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. 
  11. ^ Tonkin, Stephen F., Binocular astronomy, Springer: 124, 2007, ISBN 978-1-84628-308-6.