孫增二
孫增二（大犬座λ）是大犬座中一顆藍白色調的單獨恆星[10]。孫增二的視星等是+4.48，在無光害的場所可以用裸眼看見[2]。根據從地球觀察到的恆星視差7.70mas [1]，它與太陽的距離為424光年。由於星際塵埃的消光，在這樣的距離上它的視亮度會降低0.14等[5]。
| 觀測資料 曆元 J2000.0 | |
|---|---|
| 星座 | 大犬座 |
| 星官 | 孫（井宿） |
| 赤經 | 06h 28m 10.20747s[1] |
| 赤緯 | −32° 34′ 48.2455″[1] |
| 視星等（V） | +4.48[2] |
| 特性 | |
| 光谱分类 | B4 V[3] |
| U−B 色指数 | −0.61[2] |
| B−V 色指数 | −0.17[2] |
| 天体测定 | |
| 徑向速度 (Rv) | +41.0±4.1[4] km/s |
| 自行 (μ) | 赤经：−14.41[1] mas/yr 赤纬：+25.21[1] mas/yr |
| 视差 (π) | 7.70 ± 0.16[1] mas |
| 距离 | 424 ± 9 ly (130 ± 3 pc) |
| 绝对星等 (MV) | −0.85[5] |
| 詳細資料 | |
| 質量 | 5.7±0.3[6] M☉ |
| 表面重力 (log g) | 3.93[7] |
| 亮度 | 560[8] L☉ |
| 溫度 | 16,300[3] K |
| 自轉速度 (v sin i) | 102±9[3] km/s |
| 年齡 | 39.8±19.1[6] Myr |
| 其他命名 | |
| 參考資料庫 | |
| SIMBAD | 资料 |
這是一顆恆星光譜為B4V的B型主序星[3]。估計它的年齡是4,000萬年[6]，恆星的投影旋轉速度為102公里/秒[3]。它的質量是5.7太陽質量[6]，亮度是太陽亮度的560倍[8]，表面的有效溫度為16,300K[3]。
參考資料
- ^ 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 Johnson, H. L.; et al, UBVRIJKL photometry of the bright stars, Communications of the Lunar and Planetary Laboratory, 1966, 4 (99): 99, Bibcode:1966CoLPL...4...99J.
- ^ 3.0 3.1 3.2 3.3 3.4 3.5 Bragança, G. A.; et al, Projected Rotational Velocities and Stellar Characterization of 350 B Stars in the Nearby Galactic Disk, The Astronomical Journal, November 2012, 144 (5): 10, Bibcode:2012AJ....144..130B, arXiv:1208.1674 , doi:10.1088/0004-6256/144/5/130, 130.
- ^ Gontcharov, G. A., Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system, Astronomy Letters, November 2006, 32 (11): 759–771, Bibcode:2006AstL...32..759G, arXiv:1606.08053 , doi:10.1134/S1063773706110065.
- ^ 5.0 5.1 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.
- ^ 6.0 6.1 6.2 6.3 Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M., A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun, Monthly Notices of the Royal Astronomical Society, January 2011, 410 (1): 190–200, Bibcode:2011MNRAS.410..190T, arXiv:1007.4883 , doi:10.1111/j.1365-2966.2010.17434.x.
- ^ Castelli, F., Effective temperature and gravity c0 and beta indices for B-type stars, Astronomy and Astrophysics, November 1991, 251: 106, Bibcode:1991A&A...251..106C.
- ^ 8.0 8.1 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.
- ^ lam CMa. SIMBAD. 斯特拉斯堡天文資料中心. [2017-09-07].
- ^ 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.
外部連結
- Kaler, James N., Theta and Lambda Canis Majoris, STARS (University of Illinois), March 8, 2013 [2017-09-08], （原始内容存档于2017-02-11）.