ㄓㄣˇ宿ㄒㄧㄡˋEpsilon Corvi,ε Crv,ε Corvi)是在南天星座烏鴉座的一顆恆星,它的固有名稱Minkar /ˈmɪŋkɑːr/,源自阿拉伯語منقار 「minqar」,意思是「烏鴉的喙」[10]。它的視星等為+3.0[2], 位於距離地球318光年(97秒差距)之處[1]

軫宿二(烏鴉座ε)
軫宿二的位置(紅圈)
觀測資料
曆元 J2000
星座 烏鴉座
星官
赤經 12h 10m 07.48058s[1]
赤緯 –22° 37′ 11.1620″[1]
視星等(V) +3.024[2]
特性
光譜分類K2 III[3]
U−B 色指數+1.458[2]
B−V 色指數+1.318[2]
天體測定
徑向速度 (Rv)+4.9[4] km/s
自行 (μ) 赤經:–71.74 mas/yr
赤緯:+10.25 mas/yr
視差 (π)10.26 ± 0.16[1] mas
距離318 ± 5 ly
(97 ± 2 pc)
絕對星等 (MV)−1.82+0.15
−0.14
[5]
詳細資料
質量3.2[6] M
半徑52[7] R
表面重力 (log g)2.16[8]
溫度4320[8] K
金屬量 [Fe/H]–0.13[8] dex
自轉速度 (v sin i)1.0[6] km/s
其他命名
2 Crv、BD−21° 3487、 FK5 453、HD 105707、HIP 59316、HR 4630、SAO 180531[9]
參考資料庫
SIMBAD資料

中國,它是軫宿的第二顆星[11][12]

軫宿二是一顆紅巨星,其恆星分類為K2III。它已經耗盡了核心的氫,在演化上易經遠離主序列。它的質量約為太陽的3倍[6]。以干涉測量術量測得到這顆恆星的角直徑大約為4.99 毫角秒[13],以其估計的距離,它的真實半徑大約相當於太陽半徑的52倍[7]。表面的有效溫度4320 K[8],使其具有K型恆星特有的橙色色調[14]。它的質量大約是太陽的4倍,在其生命的大部分時間裏都是光譜類型為B5V的主序星[15]

參考資料

編輯
  1. ^ 1.0 1.1 1.2 1.3 van Leeuwen, F., Validation of the new Hipparcos reduction, Astronomy and Astrophysics, November 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 Celis S., L., Photoelectric photometry of late-type variable stars, Astronomy and Astrophysics Supplement Series, October 1975, 22: 9–17, Bibcode:1975A&AS...22....9C 
  3. ^ Houk, Nancy, Michigan catalogue of two-dimensional spectral types for the HD stars 4, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, 1979, Bibcode:1988mcts.book.....H 
  4. ^ Wielen, R.; et al, Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions, Veroeffentlichungen des Astronomischen Rechen-Instituts Heidelberg (Astronomisches Rechen-Institut Heidelberg), 1999, 35 (35): 1, Bibcode:1999VeARI..35....1W 
  5. ^ Carney, Bruce W.; et al, Rotation and Macroturbulence in Metal-Poor Field Red Giant and Red Horizontal Branch Stars, The Astronomical Journal, March 2008, 135 (3): 892–906, Bibcode:2008AJ....135..892C, S2CID 2756572, arXiv:0711.4984 , doi:10.1088/0004-6256/135/3/892 
  6. ^ 6.0 6.1 6.2 Melo, C. H. F.; et al, On the nature of lithium-rich giant stars. Constraints from beryllium abundances, Astronomy and Astrophysics, August 2005, 439 (1): 227–235, Bibcode:2005A&A...439..227M, S2CID 10580797, arXiv:astro-ph/0504133 , doi:10.1051/0004-6361:20041805 
  7. ^ 7.0 7.1 Lang, Kenneth R., Astrophysical formulae, Astronomy and astrophysics library 1 3rd, Birkhäuser, 2006 [2024-04-02], ISBN 3-540-29692-1, (原始內容存檔於2023-07-28) . The radius (R*) is given by:
     
  8. ^ 8.0 8.1 8.2 8.3 McWilliam, Andrew, High-resolution spectroscopic survey of 671 GK giants. I - Stellar atmosphere parameters and abundances, Astrophysical Journal Supplement Series, December 1990, 74: 1075–1128, Bibcode:1990ApJS...74.1075M, doi:10.1086/191527  
  9. ^ MINKAR -- Variable Star, SIMBAD (Centre de Données astronomiques de Strasbourg), [2012-01-23], (原始內容存檔於2024-04-11) 
  10. ^ Al-Sufi, Book Of Fixed Stars, Constellation: The Crow. [2024-04-02]. (原始內容存檔於2020-10-03). 
  11. ^ (中文) 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.
  12. ^ (中文) 香港太空館 - 研究資源 - 亮星中英對照表 網際網路檔案館存檔,存檔日期January 30, 2011,., Hong Kong Space Museum. Accessed on line November 23, 2010.
  13. ^ Richichi, A.; Percheron, I.; Khristoforova, M., CHARM2: An updated Catalog of High Angular Resolution Measurements, Astronomy and Astrophysics, February 2005, 431 (2): 773–777, Bibcode:2005A&A...431..773R, doi:10.1051/0004-6361:20042039  
  14. ^ The Colour of Stars, Australia Telescope, Outreach and Education (Commonwealth Scientific and Industrial Research Organisation), December 21, 2004 [2012-01-16], (原始內容存檔於2012-03-18) 
  15. ^ Kaler, James B. (Jim), Minkar, Stars (University of Illinois), [12 July 2015], (原始內容存檔於2021-04-15)