维基百科
水府一
水府一（獵戶座ν）是位於獵戶座東北部的一對聯星[11]，不要將其與變星獵戶座NU混淆[12]。水府一的視星等為4.42[2]，這足夠明亮，因此可以用肉眼直接看到。依據0.00632弧秒的年週視差[1]，這個系統的距離大約是520光年。
| 觀測資料 曆元 J2000.0 | |
|---|---|
| 星座 | 獵戶座 |
| 星官 | 水府 （參宿） |
| 赤經 | 06h 07m 34.32588s[1] |
| 赤緯 | +14° 46′ 06.5061″[1] |
| 視星等（V） | 4.42[2] |
| 特性 | |
| 光谱分类 | B3 V[3] or B3 IV[4] |
| U−B 色指数 | −0.67[2] |
| B−V 色指数 | −0.18[2] |
| 天体测定 | |
| 徑向速度 (Rv) | +24.1[5] km/s |
| 自行 (μ) | 赤经：+6.78[1] mas/yr 赤纬：−20.23[1] mas/yr |
| 视差 (π) | 6.32 ± 0.33[1] mas |
| 距离 | 520 ± 30 ly (158 ± 8 pc) |
| 軌道[6] | |
| 繞行週期 (P) | 131.211 d |
| 偏心率 (e) | 0.64 |
| 近心点 曆元 (T) | 2436475.852 JD |
| 近心點幅角 (ω) (secondary) | 6.6° |
| 半振幅 (K1) (primary) | 33.3 km/s |
| 詳細資料 | |
| ν Ori A | |
| 質量 | 6.7±0.1[4] M☉ |
| 半徑 | 4.3[7] R☉ |
| 表面重力 (log g) | 4.06[8] |
| 亮度 | 1,965[3] L☉ |
| 溫度 | 17,880[8] K |
| 金属量 [Fe/H] | −0.05[8] dex |
| 自轉速度 (v sin i) | 30[9] km/s |
| 年齡 | 26.3±5.3[4] Myr |
| 其他命名 | |
| 參考資料庫 | |
| SIMBAD | 资料 |
這是肘有一組譜線的光譜聯星系統[9]，這意味著只能分析其中一個成員的吸收譜線特徵。根據這個分量的繞行，週期為131.2天，離心率為0.64[6]。根據這個來源，主星要麼是恆星分類為B3V的B型主序星[3]， 或是已經演化成為B3IV的B型次巨星[4]。 它的角直徑為0.251mas[13]，以這個系統的距離估計，它的實際半徑約為4.3R☉（太陽半徑）[7]，質量是6.7M☉（太陽質量）[4]，光度是1,965L☉（太陽光度）[3]，大氣層表面的有效溫度為17,880K[8]。
參考資料 编辑
- ^ 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.
- ^ 2.0 2.1 2.2 2.3 Crawford, D. L.; et al, Four-color, H-beta, and UBV photometry for bright B-type stars in the northern hemisphere, The Astronomical Journal, 1971, 76: 1058, Bibcode:1971AJ.....76.1058C, doi:10.1086/111220.
- ^ 3.0 3.1 3.2 3.3 Hohle, M. M.; et al, Masses and luminosities of O- and B-type stars and red supergiants, Astronomische Nachrichten, April 2010, 331 (4): 349–360, Bibcode:2010AN....331..349H, S2CID 111387483, arXiv:1003.2335 , doi:10.1002/asna.200911355.
- ^ 4.0 4.1 4.2 4.3 4.4 Tetzlaff, N.; et al, A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun, Monthly Notices of the Royal Astronomical Society, 2011, 410 (1): 190–200, Bibcode:2011MNRAS.410..190T, S2CID 118629873, arXiv:1007.4883 , doi:10.1111/j.1365-2966.2010.17434.x.
- ^ Evans, D. S., The Revision of the General Catalogue of Radial Velocities, Batten, Alan Henry; Heard, John Frederick (编), Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30 30, University of Toronto: International Astronomical Union: 57, June 20–24, 1966, Bibcode:1967IAUS...30...57E.
- ^ 6.0 6.1 Pourbaix, D.; et al, SB9: The ninth catalogue of spectroscopic binary orbits, Astronomy and Astrophysics, 2004, 424 (2): 727–732, Bibcode:2004A&A...424..727P, S2CID 119387088, arXiv:astro-ph/0406573 , doi:10.1051/0004-6361:20041213.
- ^ 7.0 7.1 Lang, Kenneth R., Astrophysical formulae, Astronomy and astrophysics library 1 3rd, Birkhäuser, 2006 [2021-12-06], ISBN 3-540-29692-1, （原始内容于2019-05-20）.. The radius (R*) is given by:
- ^ 8.0 8.1 8.2 8.3 Gies, Douglas R.; Lambert, David L., Carbon, nitrogen, and oxygen abundances in early B-type stars, Astrophysical Journal, Part 1, March 1992, 387: 673–700, Bibcode:1992ApJ...387..673G, doi:10.1086/171116.
- ^ 9.0 9.1 Abt, Helmut A.; et al, Rotational Velocities of B Stars, The Astrophysical Journal, July 2002, 573 (1): 359–365, Bibcode:2002ApJ...573..359A, doi:10.1086/340590 .
- ^ nu. Ori. SIMBAD. 斯特拉斯堡天文資料中心.
- ^ 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.
- ^ Marett-Crosby, Michael, Twenty-Five Astronomical Observations That Changed the World: And How To Make Them Yourself, The Patrick Moore Practical Astronomy Series, Springer Science & Business Media: 93, 2013 [2021-12-06], ISBN 978-1461468004, （原始内容于2021-12-06）.
- ^ Zorec, J.; et al, Fundamental parameters of B supergiants from the BCD system. I. Calibration of the (λ_1, D) parameters into Teff, Astronomy and Astrophysics, July 2009, 501 (1): 297–320, Bibcode:2009A&A...501..297Z, S2CID 14969137, arXiv:0903.5134 , doi:10.1051/0004-6361/200811147.