房宿增一
房宿增一（拉丁文名稱為Lambda Librae）是黃道星座天秤座的聯星，拜耳名稱是天秤座λ。它是顆黯淡的恆星，視星等 +5.03，在漆黑的夜晚肉眼隱約可見[2]。年周視差10.54mas[1]，因此與太陽的距離是310光年。在這樣的距離上，星際塵埃造成的消光使它的視星等降低0.22等[6]。
| 觀測資料 曆元 J2000.0 | |
|---|---|
| 星座 | 天秤座 |
| 星官 | |
| 赤經 | 15h 53m 20.05463s[1] |
| 赤緯 | −20° 10′ 01.4177″[1] |
| 視星等（V） | 5.03[2] |
| 特性 | |
| 光譜分類 | B3 V[3] |
| U−B 色指數 | −0.584[2] |
| B−V 色指數 | −0.023[2] |
| 變星類型 | 旋轉橢球[4] |
| 天體測定 | |
| 徑向速度 (Rv) | −2.0±0.5[5] km/s |
| 自行 (μ) | 赤經：−9.81[1] mas/yr 赤緯：−26.85[1] mas/yr |
| 視差 (π) | 10.54 ± 0.91[1] mas |
| 距離 | 310 ± 30 ly (95 ± 8 pc) |
| 絕對星等 (MV) | 0.56[6] |
| 軌道[7] | |
| 繞行週期 (P) | 14.4829±0.0004 d |
| 偏心率 (e) | 0.27±0.09 |
| 近心點 曆元 (T) | 2435172.380 ± 0.664 JD |
| 近心點幅角 (ω) (secondary) | 217±17° |
| 半振幅 (K1) (primary) | 28.5±3.3 km/s |
| 詳細資料 | |
| 質量 | 5.01±0.26[8] M☉ |
| 半徑 | 3.9[9] R☉ |
| 表面重力 (log g) | 4.75 |
| 亮度 | 743[8] L☉ |
| 溫度 | 18,700[8] K |
| 金屬量 [Fe/H] | −0.27 dex |
| 自轉速度 (v sin i) | 155[10] km/s |
| 年齡 | 282[6] Myr |
| 其他命名 | |
| 參考資料庫 | |
| SIMBAD | 資料 |
它是只有單一光譜線的光譜聯星，軌道週期14.48天，離心率0.27[7]。可以見到的成員是B型主序星，光譜類型B3V[3]。它是光譜特殊的弱氦星[12]，並且是顆旋轉橢球變星[4]。估計它的半徑是太陽的3.9倍[9]，質量是太陽的5倍[8]。它是類織女的候選者，意味着它有環繞着恆星的岩屑盤引起的紅外過量特徵[13]。這個系統也是個X射線源[14]。
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 Houk, Nancy; Smith-Moore, M., Michigan catalogue of two-dimensional spectral types for the HD stars 4, Ann Arbor: Dept. of Astronomy, University of Michigan, 1978, Bibcode:1988mcts.book.....H.
- ^ 4.0 4.1 Hoffleit, Dorrit, A Catalogue of Correlations Between Eclipsing Binaries and Other Categories of Double Stars, The Journal of the American Association of Variable Star Observers, 1996, 24 (2): 105–116, Bibcode:1996JAVSO..24..105H.
- ^ 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.
- ^ 6.0 6.1 6.2 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.
- ^ 7.0 7.1 Pourbaix, D.; Tokovinin, A. A.; Batten, A. H.; Fekel, F. C.; Hartkopf, W. I.; et al, SB9: The ninth catalogue of spectroscopic binary orbits, Astronomy & Astrophysics, 2004, 424 (2): 727, Bibcode:2004A&A...424..727P, arXiv:astro-ph/0406573 , doi:10.1051/0004-6361:20041213.
- ^ 8.0 8.1 8.2 8.3 Hohle, M. M.; Neuhäuser, R.; Schutz, B. F., Masses and luminosities of O- and B-type stars and red supergiants, Astronomische Nachrichten, April 2010, 331 (4): 349, Bibcode:2010AN....331..349H, arXiv:1003.2335 , doi:10.1002/asna.200911355.
- ^ 9.0 9.1 Pasinetti Fracassini, L. E.; et al, Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) – Third edition – Comments and statistics, Astronomy and Astrophysics, February 2001, 367: 521–524, Bibcode:2001A&A...367..521P, arXiv:astro-ph/0012289 , doi:10.1051/0004-6361:20000451.
- ^ Abt, Helmut A.; et al, Rotational Velocities of B Stars, The Astrophysical Journal, 2002, 573: 359, Bibcode:2002ApJ...573..359A, doi:10.1086/340590 .
- ^ lam Lib -- Spectroscopic binary, SIMBAD Astronomical Database (Centre de Données astronomiques de Strasbourg), [2017-01-30], （原始內容存檔於2020-11-05）.
- ^ Renson, P.; Manfroid, J., Catalogue of Ap, HgMn and Am stars (PDF), Astronomy and Astrophysics, May 2009, 498 (3): 961–966 [2020-05-24], Bibcode:2009A&A...498..961R, doi:10.1051/0004-6361/200810788, （原始內容存檔 (PDF)於2020-09-15）.
- ^ 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, arXiv:0805.3936 , doi:10.1051/0004-6361:200810260.
- ^ Berghoefer, T. W.; Schmitt, J. H. M. M.; Cassinelli, J. P., The ROSAT all-sky survey catalogue of optically bright OB-type stars, Astronomy and Astrophysics Supplement, September 1996, 118: 481–494, Bibcode:1996A&AS..118..481B.
