半人馬座Xi1
半人馬座Xi1 （ξ1 Cen, ξ1 Centauri）是在南天人馬座的一顆單獨的[10] 恆星。它的視星等為裸眼可見的+4.83等[2]，年週視差14.79mas[1]，距離太陽大約221光年。 在這樣的距離上，恆星會因為中間的星際塵埃造成消光，而使視星等減弱0.1等[11]。星系NGC 4945就在半人馬座Xi1西方17 弧秒 [12]。
| 觀測資料 曆元 J2000.0 | |
|---|---|
| 星座 | 半人馬座 |
| 星官 | |
| 赤經 | 13h 03m 33.30528s[1] |
| 赤緯 | −49° 31′ 38.1518″[1] |
| 視星等（V） | +4.83[2] |
| 特性 | |
| 光譜分類 | A0 V[3] |
| U−B 色指數 | +0.014[2] |
| B−V 色指數 | +0.030[2] |
| 天體測定 | |
| 徑向速度 (Rv) | 0.00±3.70[4] km/s |
| 自行 (μ) | 赤經：−47.55[1] mas/yr 赤緯：−11.52[1] mas/yr |
| 視差 (π) | 14.79 ± 0.27[1] mas |
| 距離 | 221 ± 4 ly (68 ± 1 pc) |
| 詳細資料 [5] | |
| 質量 | 2.39 M☉ |
| 半徑 | 2.7[6] R☉ |
| 表面重力 (log g) | 4.11±0.14 |
| 亮度 | 43.2[7] L☉ |
| 溫度 | 10,462±356 K |
| 自轉速度 (v sin i) | 185[8] km/s |
| 年齡 | 125 Myr |
| 其他命名 | |
| 參考資料庫 | |
| SIMBAD | 資料 |
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這是一顆A型主序星，恆星分類為A0V[3]。他的年齡大約1億2500萬歲[5]，有相對高速的自轉，投影旋轉速度為185 km/s[8]。估計它的質量是2.4太陽質量[5]，半徑是太陽半徑的2.7倍[6]。從外層大氣的有效溫度10,462K[5]，它輻射的光度是太陽光度的43倍[7]。
參考資料
編輯- ^ 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.
- ^ 2.0 2.1 2.2 2.3 Gutierrez-Moreno, Adelina; Moreno, Hugo, A photometric investigation of the Scorpio-Centaurus association, Astrophysical Journal Supplement, June 1968, 15: 459, Bibcode:1968ApJS...15..459G, doi:10.1086/190168.
- ^ 3.0 3.1 Bauwens, E. K. J.; et al, Candidate Calibrators for the In-Orbit Spectrophotometric Calibration of the MIRI Medium Resolution Spectrograph Onboard the James Webb Space Telescope, Deustua, Susana; Oliveira, Cristina (編), The 2010 STScI Calibration Workshop (PDF), Space Telescope Science Institute, 2010 [2016-01-10].
- ^ de Bruijne, J. H. J.; Eilers, A.-C., Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project, Astronomy & Astrophysics, October 2012, 546: 14, Bibcode:2012A&A...546A..61D, arXiv:1208.3048 , doi:10.1051/0004-6361/201219219, A61.
- ^ 5.0 5.1 5.2 5.3 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, arXiv:1501.03154 , doi:10.1088/0004-637X/804/2/146.
- ^ 6.0 6.1 Pasinetti Fracassini, L. E.; et al, Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS), Astronomy and Astrophysics 3rd, February 2001, 367: 521–524, Bibcode:2001A&A...367..521P, arXiv:astro-ph/0012289 , doi:10.1051/0004-6361:20000451.
- ^ 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.
- ^ 8.0 8.1 Uesugi, Akira; Fukuda, Ichiro, Catalogue of rotational velocities of the stars, Contributions from the Institute of Astrophysics and Kwasan Observatory (University of Kyoto), 1970, Bibcode:1970crvs.book.....U.
- ^ ksi01 Cen -- Star, SIMBAD Astronomical Database (Centre de Données astronomiques de Strasbourg), [2017-01-09], （原始內容存檔於2019-05-14）.
- ^ 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, arXiv:0806.2878 , doi:10.1111/j.1365-2966.2008.13596.x.
- ^ Gontcharov, G. A., Spatial distribution and kinematics of OB stars, Astronomy Letters, November 2012, 38 (11): 694−706, Bibcode:2012AstL...38..694G, arXiv:1606.09028 , doi:10.1134/S1063773712110035.
- ^ O'Meara, Stephen James, Deep-Sky Companions: The Caldwell Objects 2nd, Cambridge University Press: 392, 2016, ISBN 1316033538.
