势四(英语:Praecipua/prɪˈsɪpjʊə/[10]小狮座4646 LMi)是小狮座最亮的恒星。它的视星等为3.83等,光谱类型为K0+III-IV,是在红团簇星中的一颗巨星[9]。依据视差的测量,它与太阳的距离约为95光年。它疑似为变星,振幅仅有0.05星等[3]

势四(小狮座46)
势四的位置(红圈处)
观测资料
历元 J2000
星座 小狮座
星官 势(紫微垣
赤经 10h 53m 18.70487s[1]
赤纬 +34° 12′ 53.5375″[1]
视星等(V) 3.83[2] (3.79–3.84[3])
特性
光谱分类K0+ III-IV[4]
天体测定
自行 (μ) 赤经:+92.02[1] mas/yr
赤纬:–285.82[1] mas/yr
视差 (π)34.38 ± 0.21[1] mas
距离94.9 ± 0.6 ly
(29.1 ± 0.2 pc)
绝对星等 (MV)+1.45[5]
详细资料
质量1.69[6] M
半径8.22 ± 0.22[2] R
表面重力 (log g)2.96[2]
亮度34 ± 2[2] L
温度4,670[2] K
金属量 [Fe/H]−0.20[7] dex
自转速度 (v sin i)1.81[8] km/s
年龄6.76[9] Gyr
其他命名
Praecipua、46 LM、BD+34 2172、FK5 412、HD 94264、HIP 53229, HR 4247、SAO 62297
参考数据库
SIMBAD资料

命名法

编辑

小狮座46的名称来自佛兰斯蒂德命名法。它有时会依据1801年弗朗西斯·贝利的星表,标示为小狮座o(不是ο)。合理的推测认为它在拜耳命名法中是α星,但是贝利决定在他的星表中标示每一颗比4.5等亮的恒星时,错误的将α写成o,所以小狮座有较暗的β星(势增四,视星等4.2等),却没有最亮的α星[11]

它的传统名称是Praecipua,这是源自拉丁文的名称,意思是“首领”(小狮座为首的恒星)[12]。这个名字最初可能是指势增十一(小狮座37,视星等4.7),后来被错误的转移到了这颗恒星上[13]。在2016年,国际天文学联合会(IAU)组织的IAU恒星名称工作组(WGSN)[14],对恒星的专有名称进行分类和标准化。WGSN于2017年6月30日核定了这颗恒星的名称为Praecipua,并将其列入IAU核定的恒星名称清单中[10]

势四是中国的名称,意思是星官势的第四颗星。在传统的中国天文学体系中属于紫微垣

相关条目

编辑

参考资料

编辑
  1. ^ 1.0 1.1 1.2 1.3 1.4 van Leeuwen, F., Validation of the new Hipparcos reduction, Astronomy and Astrophysics, November 2007, 474 (2): 653–664, Bibcode:2007A&A...474..653V, S2CID 18759600, arXiv:0708.1752 , doi:10.1051/0004-6361:20078357 
  2. ^ 2.0 2.1 2.2 2.3 2.4 Piau, L.; et al, Surface convection and red-giant radius measurements, Astronomy and Astrophysics, February 2011, 526: A100, Bibcode:2011A&A...526A.100P, S2CID 118533297, arXiv:1010.3649 , doi:10.1051/0004-6361/201014442 
  3. ^ 3.0 3.1 Samus, N. N.; Durlevich, O. V.; et al. VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007–2013). VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 2009, 1. Bibcode:2009yCat....102025S. 
  4. ^ Keenan, Philip C.; McNeil, Raymond C. The Perkins catalog of revised MK types for the cooler stars. Astrophysical Journal Supplement Series. 1989, 71: 245. Bibcode:1989ApJS...71..245K. doi:10.1086/191373. 
  5. ^ Mullan, D. J.; MacDonald, J. Onset of Mass Loss in Red Giants: Association with an Evolutionary Event. The Astrophysical Journal. 2003, 591 (2): 1203. Bibcode:2003ApJ...591.1203M. doi:10.1086/375446 . 
  6. ^ Lyubimkov, L. S.; Poklad, D. B. Determining the effective temperatures of G- and K-type giants and supergiants based on observed photometric indices. Kinematics and Physics of Celestial Bodies. 2014, 30 (5): 244. Bibcode:2014KPCB...30..244L. S2CID 118618820. arXiv:1412.6950 . doi:10.3103/S0884591314050055. 
  7. ^ Wittenmyer, Robert A.; Gao, Dongyang; Hu, Shao Ming; Villaver, Eva; Endl, Michael; Wright, Duncan. The Weihai Observatory Search for Close-in Planets Orbiting Giant Stars. Publications of the Astronomical Society of the Pacific. 2015, 127 (956): 1021. Bibcode:2015PASP..127.1021W. S2CID 117305333. arXiv:1507.06051 . doi:10.1086/683258. 
  8. ^ Hekker, S.; Meléndez, J. Precise radial velocities of giant stars. III. Spectroscopic stellar parameters. Astronomy and Astrophysics. 2007, 475 (3): 1003. Bibcode:2007A&A...475.1003H. S2CID 10436552. arXiv:0709.1145 . doi:10.1051/0004-6361:20078233. 
  9. ^ 9.0 9.1 Soubiran, C.; Bienaymé, O.; Mishenina, T. V.; Kovtyukh, V. V. Vertical distribution of Galactic disk stars. IV. AMR and AVR from clump giants. Astronomy and Astrophysics. 2008, 480 (1): 91–101. Bibcode:2008A&A...480...91S. S2CID 16602121. arXiv:0712.1370 . doi:10.1051/0004-6361:20078788. 
  10. ^ 10.0 10.1 Naming Stars. IAU.org. [2017-12-16]. (原始内容存档于2020-04-11). 
  11. ^ Wagman, Morton. Lost Stars. Blacksburg, Virginia: McDonald and Woodward. 2003. ISBN 0-939923-78-5. 
  12. ^ Allen, R. H. Star Names: Their Lore and Meaning Reprint. New York, NY: Dover Publications Inc. 1963: 264. ISBN 0-486-21079-0. 
  13. ^ Leo Minor: The little lion页面存档备份,存于互联网档案馆)- Ian Ridpath's Star Tales
  14. ^ IAU Working Group on Star Names (WGSN). [2016-05-22]. (原始内容存档于2019-06-26).