周增七的英文名字来自拉丁文ι Serpentis,是一颗四合星[7],位置在巨蛇座的头部。它与地球的距离大约是190光年 [1]

周增七(巨蛇座ι)
周增七的位置(红色圈)
观测资料
历元 J2000
星座 Serpens
星官
赤经 15h 41m 33.05469s[1]
赤纬 19° 40′ 13.4380″[1]
视星等(V) 4.51[2]
特性
光谱分类B9V + A1V[3]
B−V 色指数+0.06[2]
天体测定
径向速度 (Rv)−17.20[4] km/s
自行 (μ) 赤经:-60.86[1] mas/yr
赤纬:-43.69[1] mas/yr
视差 (π)17.16 ± 0.67[1] mas
距离190 ± 7 ly
(58 ± 2 pc)
绝对星等 (MV)+0.69[5]
轨道[6]
绕行周期 (P)8015.0 days
半长轴 (a)0.21033"
偏心率 (e)0.0941
倾斜角 (i)83.608°
升交点黄经 (Ω)69.684°
近心点幅角 (ω)
(secondary)
80.5°
详细资料
A
质量1.999[3] M
B
质量1.984[3] M
其他命名
ι Ser、​21 Serpentis、​BD+20° 3138、​GC 21102、​HD 140159、​HIP 76852、​HR 5842、​SAO 101682、​ADS 9744、​CCDM J15416+1940[2]
参考资料库
SIMBAD资料

系统的中心是一对光谱联星周增七A周增七B。这两颗都是矮星,并且视星等都是+5.3等。这对联星的轨道周期有人报告是11年[8]或22年[6]。它曾是被发现的第一对天测联星,但是现在已经得到解决,并且获得了视觉上的轨道[6]

它有两颗视觉伴星,距离143角秒,视星等13等的周增七C,与距离151角秒,视星等12等的周增七D

参考资料

编辑
  1. ^ 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 [2018-06-28]. Bibcode:2007A&A...474..653V. arXiv:0708.1752 . doi:10.1051/0004-6361:20078357. (原始内容存档于2019-03-28).  Vizier catalog entry页面存档备份,存于互联网档案馆
  2. ^ 2.0 2.1 2.2 Iota Serpentis. SIMBAD Astronomical Database. [2015-10-17]. 
  3. ^ 3.0 3.1 3.2 Martin, C; Mignard, F; Hartkopf, W. I; McAlister, H. A. Mass determination of astrometric binaries with Hipparcos. III. New results for 28 systems. Astronomy and Astrophysics Supplement. 1998, 133 (2): 149. Bibcode:1998A&AS..133..149M. doi:10.1051/aas:1998459. 
  4. ^ Evans, D. S. Batten, Alan Henry; Heard, John Frederick , 编. Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30. Determination of Radial Velocities and their Applications 30 (University of Toronto: International Astronomical Union). June 20–24, 1966: 57. Bibcode:1967IAUS...30...57E.  参数|journal=与模板{{cite conference}}不匹配(建议改用{{cite journal}}|book-title=) (帮助); |contribution=被忽略 (帮助)
  5. ^ Anderson, E.; Francis, Ch., XHIP: An extended hipparcos compilation, Astronomy Letters, 2012, 38 (5): 331, Bibcode:2012AstL...38..331A, arXiv:1108.4971 , doi:10.1134/S1063773712050015. 
  6. ^ 6.0 6.1 6.2 Muterspaugh, Matthew W.; et al. The Phases Differential Astrometry Data Archive. II. Updated Binary Star Orbits and a Long Period Eclipsing Binary. The Astronomical Journal. 2010, 140 (6): 1623–1630. Bibcode:2010AJ....140.1623M. arXiv:1010.4043 . doi:10.1088/0004-6256/140/6/1623. 
  7. ^ 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. 
  8. ^ van den Bos, W. H. Note on the Double Star Iota Serpentis. Monthly Notes of the Astronomical Society of Southern Africa. 1965, 24: 123. Bibcode:1965MNSSA..24..123V.