座旗五
御夫座的恆星
座旗五（ψ2Aurigae/御夫座ψ2），是御夫座的一顆恆星。視星等4.79[2]，以裸眼觀測較為黯淡。因為星際氣體及塵埃而產生的消光，其亮度減少了0.07[5]。
 | |
| 觀測資料 曆元 J2000 | |
|---|---|
| 星座 | 御夫座 |
| 星官 | |
| 赤經 | 06h 39m 19.82634s[1] |
| 赤緯 | +42° 29′ 19.9617″[1] |
| 視星等（V） | 4.79[2] |
| 特性 | |
| 光譜分類 | K3 III[3] or K3 Iab:[4] |
| U−B 色指數 | +1.30[2] |
| B−V 色指數 | +1.23[2] |
| R−I 色指數 | 0.6 |
| 天體測定 | |
| 徑向速度 (Rv) | 16.09 ± 0.19[5] km/s |
| 自行 (μ) | 赤經：-0.87[1] mas/yr 赤緯：-54.97[1] mas/yr |
| 視差 (π) | 7.84 ± 0.29[1] mas |
| 距離 | 420 ± 20 ly (128 ± 5 pc) |
| 詳細資料 | |
| 半徑 | 27[6] R☉ |
| 表面重力 (log g) | 2.30[7] |
| 溫度 | 4,410[7] K |
| 金屬量 [Fe/H] | –0.10[7] dex |
| 自轉速度 (v sin i) | 1.0[8] km/s |
| 其他命名 | |
根據多項研究表明，由恆星光譜可得座旗五為一顆 K3 III 型巨星[3]，可是根據 2003 年的研究上座旗五被分類為 K3 Iab 型的超巨星[4][9]。經過周邊昏暗修正的角直徑測量數據為 1.97 ± 0.02 mas[10]。估計這顆恆星距離[1]地球為 27 倍的太陽半徑[6]。
參考資料
- ^ 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, Floor, Validation of the new Hipparcos reduction, Astronomy and Astrophysics, November 2007, 474 (2): 653–664, Bibcode:2007A&A...474..653V, arXiv:0708.1752v1
, doi:10.1051/0004-6361:20078357. Note: see VizieR catalogue I/311 Archive.is的存檔，存檔日期2012-12-05.
- ^ 2.0 2.1 2.2 2.3 Johnson, H. L.; et al, UBVRIJKL photometry of the bright stars, Communications of the Lunar and Planetary Laboratory, 1966, 4 (99), Bibcode:1966CoLPL...4...99J.
- ^ 3.0 3.1 Herbig, George H.; Spalding, John F., Jr., Axial Rotation and Line Broadening in Stars of Spectral Types F0-K5, Astrophysical Journal, January 1955, 121: 118, Bibcode:1955ApJ...121..118H, doi:10.1086/145969.
- ^ 4.0 4.1 Kidger, Mark R.; Martín-Luis, Fabiola, High-Precision Near-Infrared Photometry of a Large Sample of Bright Stars Visible from the Northern Hemisphere, The Astronomical Journal, June 2003, 125 (6): 3311–3333, Bibcode:2003AJ....125.3311K4 請檢查
|bibcode=值 (幫助), doi:10.1086/374996. - ^ 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, arXiv:astro-ph/0409579 , doi:10.1051/0004-6361:20041272.
- ^ 6.0 6.1 Lang, Kenneth R., Astrophysical formulae, Astronomy and astrophysics library 1 3, Birkhäuser, 2006 [2013-12-16], ISBN 3-540-29692-1, （原始內容存檔於2013-06-22）. The radius (R*) is given by:
- ^ 7.0 7.1 7.2 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.
- ^ De Medeiros, J. R.; et al, Rotation and lithium in single giant stars, Astronomy and Astrophysics, November 2000, 363: 239–243, Bibcode:2000A&A...363..239D, arXiv:astro-ph/0010273 .
- ^ 9.0 9.1 50 Aur -- Star in double system, SIMBAD Astronomical Database (Centre de Données astronomiques de Strasbourg), [2012-08-24], （原始內容存檔於2021-07-30）.
- ^ 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.
