拉卡伊9352

拉卡伊9352(Lac 9352)是位於南天南魚座的一顆紅矮星視星等為7.34等[4]。這顆恒星太暗,即使在最良好的視相條件下,肉眼也無法觀察到。視差量測出它距離地球大約10.74光年(3.29秒差距[1],是距離太陽系最近的第11個恒星系[13],是星座南魚座最接近地球的恒星。ChView模擬[14]顯示它最近的鄰居是寶瓶座EZ三合星系統,距離它大約4.1光年遠。

拉卡伊9352 (Lacaille 9352)
Nearby Stars (14ly Radius).svg
太陽系附近,包括拉卡伊9352在內的太陽系附近恆星分布圖。
觀測資料
曆元 J2000
星座 南魚座
星官
赤經 23h 05m 52.03604s[1]
赤緯 −35° 51′ 11.0475″[1]
視星等(V) 7.34[2]
特性
光谱分类M0.5V[3]
U−B 色指数+1.18[4]
B−V 色指数+1.50[4]
变星类型疑似[5]
天体测定
徑向速度 (Rv)+9.7[6] km/s
自行 (μ) 赤经:+6,765.995[7] mas/yr
赤纬:+1,330.388[7] mas/yr
视差 (π)304.1354 ± 0.0200[8] mas
距离10.7241 ± 0.0007 ly
(3.288 ± 0.0002 pc)
绝对星等 (MV)9.8[9]
詳細資料
質量0.486 ± 0.012[10] M
半徑0.470 ± 0.001[10] R
表面重力 (log g)4.78[10]
亮度0.0367±0.0022[10] L
溫度3,692±57[10] K
金属量 [Fe/H]−0.22 ± 0.09[11] dex
自轉速度 (v sin i)1[6] km/s
年齡4.57[12] Gyr
其他命名
HD 217987, CD -36°15693 GCTP 5584, GJ 887, LHS 70, SAO 214301, LTT 9348, LFT 1758, Cordoba 31353, NSV 14420, HIP 114046, UGPMF 591.[2]

性質编辑

這顆恒星擁有已知的第四高的自行[15](1881年班傑明·古爾德首次注意到這一點[16]。),每年總共移動6.9弧秒。然而,因為在一個弧度中有3600弧秒,這仍然是一個非常小的整體運動。這顆恒星的空間速度成分是(U, V, W) = (−93.9, −14.1, −51.4) km/s[17]。如果徑向速度 ('Vr')等於+9.7公里/秒,那麼大約2,700年前拉卡伊9352距離太陽的最近,約為10.63 ly(3.26 pc)[18]

拉卡伊9352的光譜分類為M0.5V的類型 [3],這表明它是被稱為紅矮星的主序恒星。這是第一顆量測角直徑的紅矮星[19],其物理直徑約為太陽半徑的46%[3]。它大約擁有太陽質量的一半[3],表面的有效溫度約為3,626K[3]

行星系编辑

2020年6月,報告了兩顆超級地球行星,以及第三個可能是由於恒星活動造成,週期為50.7天的訊號。然而,如果這真的是顆行星,它可能位於適居帶內。它們是用徑向速度法從智利HARPS和夏威夷HIRES的觀測中檢測出來的 [20][21]

拉卡伊9352的行星系
成員
(依恆星距離)
质量 半長軸
(AU)
轨道周期
()
離心率 傾角 半径
b ≥ 4.2±0.6 M 0.068±0.002 9.262±0.001 0.09+0.09
−0.06
? ?
c ≥ 7.6±1.2 M 0.120±0.004 21.789+0.004
−0.005
0.22+0.09
−0.10
? ?
d (未确认) ≳ 8.3 M ~0.21 ~50.7 0.25+0.20
−0.15

相關條目编辑

參考資料编辑

  1. ^ 1.0 1.1 1.2 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 LACAILLE 9352 -- Pre-main sequence Star. SIMBAD. Centre de Données astronomiques de Strasbourg. [2010-01-20]. 
  3. ^ 3.0 3.1 3.2 3.3 3.4 Demory, Brice-Olivier; Ségransan, Damien; Forveille, Thierry; Queloz, Didier; Beuzit, Jean-Luc; Delfosse, Xavier; Di Folco, Emmanuel; Kervella, Pierre; Le Bouquin, Jean-Baptiste; Perrier, Christian; Benisty, Myriam; Duvert, Gilles; Hofmann, Karl-Heinz; Lopez, Bruno; Petrov, Romain. Mass-radius relation of low and very low-mass stars revisited with the VLTI. Astronomy and Astrophysics. October 2009, 505 (1): 205–215. Bibcode:2009A&A...505..205D. S2CID 14786643. arXiv:0906.0602 . doi:10.1051/0004-6361/200911976. 
  4. ^ 4.0 4.1 4.2 Cousins, A. W. J. UBV photometry of some southern stars. Monthly Notes of the Astronomical Society of Southern Africa. 1973, 32: 11. Bibcode:1973MNSSA..32...11C. 
  5. ^ Micela, G.; Pye, J.; Sciortino, S. Coronal properties of nearby old disk and halo dM stars. Astronomy and Astrophysics. April 1997, 320: 865–877. Bibcode:1997A&A...320..865M. 
  6. ^ 6.0 6.1 Torres, G. R.; et al. Search for associations containing young stars (SACY). I. Sample and searching method. Astronomy and Astrophysics. December 2006, 460 (3): 695–708. Bibcode:2006A&A...460..695T. S2CID 16080025. arXiv:astro-ph/0609258 . doi:10.1051/0004-6361:20065602. 
  7. ^ 7.0 7.1 Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne, J. H. J.; et al. Gaia Data Release 2. Summary of the contents and survey properties. Astronomy & Astrophysics. 2018. Bibcode:2018A&A...616A...1G. arXiv:1804.09365 . doi:10.1051/0004-6361/201833051.  VizieR中此天体在盖亚望远镜第二批数据发布的记录
  8. ^ Brown, A. G. A.; et al. Gaia Early Data Release 3: Summary of the contents and survey properties. Astronomy & Astrophysics. 2021, 649: A1. Bibcode:2021A&A...649A...1G. S2CID 227254300. arXiv:2012.01533 . doi:10.1051/0004-6361/202039657 .  已忽略未知参数|collaboration= (帮助) (勘误: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  9. ^ Murdin, Paul (编). Encyclopedia of Astronomy and Astrophysics. Bristol: Institute of Physics Publishing. November 2000. Bibcode:2000eaa..bookE5158.. ISBN 0333750888. doi:10.1888/0333750888/5158. absolute magnitude is 9.8  |chapter=被忽略 (帮助)
  10. ^ 10.0 10.1 10.2 10.3 10.4 Rabus, Markus; Lachaume, Régis; Jordán, Andrés; Brahm, Rafael; Boyajian, Tabetha; Von Braun, Kaspar; Espinoza, Néstor; Berger, Jean-Philippe; Le Bouquin, Jean-Baptiste; Absil, Olivier. A discontinuity in the Teff–radius relation of M-dwarfs. Monthly Notices of the Royal Astronomical Society. 2019, 484 (2): 2674–2683. Bibcode:2019MNRAS.484.2674R. S2CID 119189542. arXiv:1901.08077 . doi:10.1093/mnras/sty3430. 
  11. ^ López-Morales, Mercedes. On the Correlation between the Magnetic Activity Levels, Metallicities, and Radii of Low-Mass Stars. The Astrophysical Journal. May 2007, 660 (1): 732–739. Bibcode:2007ApJ...660..732L. S2CID 119530297. arXiv:astro-ph/0701702 . doi:10.1086/513142. 
  12. ^ Yee, Samuel W.; Petigura, Erik A.; von Braun, Kaspar. Precision Stellar Characterization of FGKM Stars using an Empirical Spectral Library. The Astrophysical Journal. 2017, 836 (1): 77. Bibcode:2017ApJ...836...77Y. S2CID 6302522. arXiv:1701.00922 . doi:10.3847/1538-4357/836/1/77. 
  13. ^ Research Consortium on Nearby Stars. The One Hundred Nearest Star Systems. Georgia State University. [2010-01-20]. (原始内容存档于2012-05-13). 
  14. ^ Solstation and ChView. [2010-04-20]. (原始内容存档于2012-02-26). 
  15. ^ High Proper Motion Stars in the Hipparcos Catalogue. European Space Agency. July 1, 2007 [2010-01-20]. 
  16. ^ Gould, B. A. Corrigenda in the Uranometria Argentina. Star with large proper motion. Astronomische Nachrichten. 1881, 100 (1): 7–10. Bibcode:1881AN....100....7G. doi:10.1002/asna.18811000104. 
  17. ^ ARICNS star page of Lacaille 9352. Astronomisches Rechen-Institut Heidelberg. [2010-04-16]. 
  18. ^ Annotations on NAME LACAILLE 9352 object. SIMBAD. Centre de Données astronomiques de Strasbourg. [2010-04-16]. 
  19. ^ Glindemann, Andreas; Paresce, Francesco. Giant Eyes for the VLT Interferometer. European Southern Observatory. [2010-01-20]. 
  20. ^ Jeffers, S. V.; Dreizler, S.; Barnes, J. R.; Haswell, C. A.; Nelson, R. P.; Rodríguez, E.; López-González, M. J.; Morales, N.; Luque, R.; et al, A multiple planet system of super-Earths orbiting the brightest red dwarf star GJ887, Science, 2020, 368 (6498): 1477–1481, Bibcode:2020Sci...368.1477J, PMID 32587019, S2CID 220075207, arXiv:2006.16372 , doi:10.1126/science.aaz0795 
  21. ^ Why boring could be good for this star's two intriguing planets. Nature. [2020-06-30]. 

外部連結编辑