军井二
军井二（天兔座κ），来自拉丁化的名字是κ Leporis，是在南天星座天兔座的一个联星系统[10]。这对恒星的视星等分别为4.43和7.00；前者的亮度足以用肉眼看到。截至2000年，它们的角距离为2.179弧秒，位置角为357.3°。基于从地球量测的年周视差为4.48mas[1]，这个系统距离太阳大约730光年。系统以20.8公里/秒的径向速度远离太阳[5]。
| 观测资料 历元 J2000.0 | |
|---|---|
| 星座 | 天兔座 |
| 星官 | |
| 赤经 | 05h 13m 13.87761s[1] |
| 赤纬 | −12° 56′ 28.6463″[1] |
| 视星等（V） | 4.43 + 7.00[2] |
| 特性 | |
| 光谱分类 | B9 V[3] |
| U−B 色指数 | −0.34[4] |
| B−V 色指数 | −0.10[4] |
| 天体测定 | |
| 径向速度 (Rv) | +20.8±1.0[5] km/s |
| 自行 (μ) | 赤经：−12.29[1] mas/yr 赤纬：−0.79[1] mas/yr |
| 视差 (π) | 4.48 ± 0.58[1] mas |
| 距离 | approx. 730 ly (approx. 220 pc) |
| 绝对星等 (MV) | −2.34[6] |
| 详细资料 [3] | |
| κ Lep A | |
| 质量 | 4.86±0.39 M☉ |
| 半径 | 2.6[7] R☉ |
| 表面重力 (log g) | 3.44[8] |
| 亮度 | 1,346 L☉ |
| 温度 | 11,588 K |
| 金属量 [Fe/H] | −0.07[8] dex |
| 自转速度 (v sin i) | 135 km/s |
| 其他命名 | |
| 参考数据库 | |
| SIMBAD | 资料 |
系统中较亮的蓝白色成员A，是B型主序星，恒星分类为B9V[3]。它的质量几乎是太阳质量的5倍[3]，半径是太阳半径的2.6倍[7]。这颗恒星在11,588 K的有效温度下，从其光球发出的辐射是太阳光度的1,346倍[3]。它在12μm的波长下显示出红外过量，使其成为星周岩屑盘的候选宿主[11]。
参考资料
- ^ 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, S2CID 18759600, arXiv:0708.1752
, doi:10.1051/0004-6361:20078357.
- ^ Fabricius, C.; Makarov, V. V., Two-colour photometry for 9473 components of close Hipparcos double and multiple stars, Astronomy and Astrophysics, April 2000, 356: 141–145, Bibcode:2000A&A...356..141F.
- ^ 3.0 3.1 3.2 3.3 3.4 Zorec, J.; Royer, F., Rotational velocities of A-type stars. IV. Evolution of rotational velocities, Astronomy & Astrophysics, January 2012, 537: A120, Bibcode:2012A&A...537A.120Z, S2CID 55586789, arXiv:1201.2052 , doi:10.1051/0004-6361/201117691.
- ^ 4.0 4.1 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.
- ^ 5.0 5.1 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, S2CID 59451347, arXiv:1208.3048 , doi:10.1051/0004-6361/201219219, A61.
- ^ Anderson, E.; Francis, Ch., XHIP: An extended hipparcos compilation, Astronomy Letters, 2012, 38 (5): 331, Bibcode:2012AstL...38..331A, S2CID 119257644, arXiv:1108.4971 , doi:10.1134/S1063773712050015.
- ^ 7.0 7.1 Pasinetti Fracassini, L. E.; et al, Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS), Astronomy and Astrophysics Third, February 2001, 367: 521–24, Bibcode:2001A&A...367..521P, S2CID 425754, arXiv:astro-ph/0012289 , doi:10.1051/0004-6361:20000451.
- ^ 8.0 8.1 Saffe, C.; Gómez, M.; Pintado, O.; González, E., Spectroscopic metallicities of Vega-like stars, Astronomy and Astrophysics, October 2008, 490 (1): 297–305, Bibcode:2008A&A...490..297S, S2CID 15059920, arXiv:0805.3936 , doi:10.1051/0004-6361:200810260.
- ^ kap Lep. SIMBAD. 斯特拉斯堡天文资料中心. [2017-08-18].
- ^ 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.
- ^ Mannings, Vincent; et al, Candidate Main-Sequence Stars with Debris Disks: A New Sample of Vega-like Sources, The Astrophysical Journal, 1998, 497 (1): 330–341, Bibcode:1998ApJ...497..330M, CiteSeerX 10.1.1.502.7594 , S2CID 122421281, doi:10.1086/305432.
