维基百科

Groombridge 1618

格龙布里奇 1618是位于大熊座的一颗恒星。它的视星等为+6.6，处于或低于普通观察者肉眼可见恒星的阈值。它距离地球相对较近，距离为15.89光年（4.87光年）。这是一颗光谱类型为K7.5 Ve的主序星，质量仅为太阳的67% 。

Groombridge 1618
Groombridge 1618 is located in the constellation Ursa Major.
Groombridge 1618 is located in the constellation Ursa Major.
Groombridge 1618
Groombridge 1618在大熊座的位置

观测资料
历元 J2000.0
星座 大熊座
星官
赤经 10h 11m 22.13995s[1]
赤纬 +49° 27′ 15.2510″[1]
视星等（V） +6.60[2]
特性
光谱分类K7.5 Ve[3]
U−B 色指数+1.27[2]
B−V 色指数+1.34[2]
变星类型BY Dra,[4] Flare star[5]
天体测定
径向速度 (Rv)−26.48±0.12[1] km/s
自行 (μ) 赤经：−1363.287±0.016 mas/yr
赤纬：−505.770±0.020 mas/yr
视差 (π)205.3148 ± 0.0224[1] mas
距离15.886 ± 0.002 ly
(4.8706 ± 0.0005 pc)
绝对星等 (MV)8.11[6]
详细资料
质量0.670±0.033[7] M☉
半径0.605±0.02[7] R☉
表面重力 (log g)4.51;[8] 4.70[7]
亮度 (bolometric)0.15[9] L☉
亮度 (visual, LV)0.049 L☉
温度3,970[8] K
金属量 [Fe/H]–0.03[8] dex
自转速度 (v sin i)2.8[10] km/s
年龄6.6[9] Gyr
其他命名
BD+50° 1725、​GJ 380、​HD 88230、​HIP 49908、​SAO 43223、​LFT 696、​IRAS 10082+4942[11]
参考数据库
SIMBAD资料

特性

Stephen Groombridge（英语：Stephen Groombridge）

格龙布里奇 1618的恒星分类为K8V，这意味着它是一颗K型主序星，通过在其核心聚变氢来产生能量。它的质量是太阳的67%，半径是太阳的61%，[7] 但辐射的能量只有太阳的15%，可见光光谱中的能量也只有太阳的 4.6% 。恒星光球层的有效表面温度约为 4,000 K，呈现橙色。

它也是磁场强度为 750 G 的天龙座BY型变星[4]。色球相对不活跃[12] 并产生可与太阳耀斑媲美的星斑。然而，像UV Ceti一样，它已被观察到作为耀星经历了光度的增加。a[5]

行星搜索

红外空间天文台对这颗恒星的过量红外辐射的搜索结果是否定的，这意味着格龙布里奇 1618附近没有碎片盘（例如织女星）。[13] 然而，使用赫雪尔太空望远镜进行的观测显示存在低温碎片盘。数据可以用温度低于 22 K 的粗糙、高反射性尘埃环模拟，环绕主恒星至少51个天文单位。[9] 如果这颗星确实有伴星，天体测量测量结果似乎将 3-12 倍木星质量的上限置于这样一个假设的物体上（轨道周期在 5-50 年的范围内）。[14]

观测结果倾向于将周期为 122天的单个显著物体作为行星物体，其最小质量是木星的 4 倍。这颗候选行星从未得到证实，作者发现的信号可能是由于恒星年轻时的内在恒星活动。如果得到证实，这颗行星将位于恒星的宜居带内。[15] [note 1]

2010 年使用配备自适应光学系统的多镜面望远镜对该系统进行的检查未能检测到行星伴星。[17]

这颗恒星的宜居带定义为类地行星上可能存在液态水的区域，半径为0.26–0.56个天文单位，其中1个天文单位是地球到太阳的平均距离。[18]

根据美国宇航局戈达德太空飞行中心的分析，这颗恒星是附近五颗K型恒星之一，属于类太阳恒星和M型恒星之间演化生命可能性的“最佳点”。[19]

参见

注释

  1. ^   [16] when used to calculate the stellar flux reaching the outer atmosphere of an Earth-like planet orbiting Groombridge 1618 at the Inner Habitable Zone edge - the Runaway Greenhouse limit gives a   of 0.9397 or 93.97% the stellar flux reaching the top of Earth's atmosphere. By applying the previously calculated stellar flux and the known 15% luminosity of Groombridge 1618 into the equation,  ,[16] the distance of the Inner HZ - Runaway Greenhouse limit from Groombridge 1618 can be calculated as  .

参考资料

  1. ^ 1.0 1.1 1.2 1.3 Vallenari, A.; et al. Gaia Data Release 3. Summary of the content and survey properties. Astronomy & Astrophysics. 2022. arXiv:2208.00211  . doi:10.1051/0004-6361/202243940  .  已忽略未知参数|collaboration= (帮助) Gaia DR3 record for this source at VizieR.
  2. ^ 2.0 2.1 2.2 Argue, A. N., UBV photometry of 550 F, G and K type stars, Monthly Notices of the Royal Astronomical Society, 1966, 133 (4): 475–493, Bibcode:1966MNRAS.133..475A, doi:10.1093/mnras/133.4.475   
  3. ^ Lépine, Sébastien; et al, A Spectroscopic Catalog of the Brightest (J < 9) M Dwarfs in the Northern Sky, The Astronomical Journal, 2013, 145 (4): 102, Bibcode:2013AJ....145..102L, S2CID 117144290, arXiv:1206.5991  , doi:10.1088/0004-6256/145/4/102. 
  4. ^ 4.0 4.1 Gudel, M., Radio and X-ray emission from main-sequence K stars, Astronomy and Astrophysics, October 1992, 264 (2): L31–L34, Bibcode:1992A&A...264L..31G. 
  5. ^ 5.0 5.1 Andrillat, Y.; Morguleff, N., Hack, Margherita , 编, Three potassium-flare stars, Proceedings of the Colloquium, held in Trieste, June 13–17, 1966, Trieste, 1967: 160, Bibcode:1967lts..conf..160A. 
  6. ^ Holmberg, J.; et al, The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics, Astronomy and Astrophysics, July 2009, 501 (3): 941–947, Bibcode:2009A&A...501..941H, S2CID 118577511, arXiv:0811.3982  , doi:10.1051/0004-6361/200811191. 
  7. ^ 7.0 7.1 7.2 7.3 Ségransan, Damien; Kervella, Pierre; Forveille, Thierry; Queloz, Didier. First radius measurements of very low mass stars with the VLTI. Astronomy and Astrophysics. 2003, 397 (3): L5–L8. Bibcode:2003A&A...397L...5S. S2CID 10748478. arXiv:astro-ph/0211647  . doi:10.1051/0004-6361:20021714. 
  8. ^ 8.0 8.1 8.2 Woolf, Vincent M.; Wallerstein, George. Metallicity measurements using atomic lines in M and K dwarf stars. Monthly Notices of the Royal Astronomical Society. January 2005, 356 (3): 963–968. Bibcode:2005MNRAS.356..963W. S2CID 15664454. arXiv:astro-ph/0410452  . doi:10.1111/j.1365-2966.2004.08515.x.  See table 3.
  9. ^ 9.0 9.1 9.2 Eiroa, C.; et al, Herschel discovery of a new class of cold, faint debris discs, Astronomy & Astrophysics, December 2011, 536: L4, Bibcode:2011A&A...536L...4E, S2CID 14234038, arXiv:1110.4826  , doi:10.1051/0004-6361/201117797. 
  10. ^ 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. 
  11. ^ NSV 4765 -- Flare Star. SIMBAD. Centre de Données astronomiques de Strasbourg. [2013-08-01]. （原始内容存档于2022-12-05）. 
  12. ^ Byrne, P. B.; Doyle, J. G., Activity in late-type stars. VII - Chromospheric and transition region line fluxes in 2 dM and 1 dM(e) stars, Astronomy and Astrophysics, November 1990, 238 (1–2): 221–226, Bibcode:1990A&A...238..221B. 
  13. ^ Laureijs, R. J.; et al. A 25 micron search for Vega-like disks around main-sequence stars with ISO (PDF). Astronomy & Astrophysics. 2002, 387 (1): L285–L293 [2023-03-20]. Bibcode:2002A&A...387..285L. doi:10.1051/0004-6361:20020366  . hdl:1887/7333. （原始内容存档 (PDF)于2017-08-09）. 
  14. ^ Hershey, J. L.; Borgman, E. R. Upper Limits on the Mass of a Dark Companion of Groombridge 1618 from the 40-year Sproul Plate Series. Bulletin of the American Astronomical Society. 1978, 10: 630. Bibcode:1978BAAS...10..630H. 
  15. ^ Marcy, Geoffrey W.; Benitz, Karsten J. A search for substellar companions to low-mass stars. Astrophysical Journal, Part 1. 1989, 344 (1): 441–453. Bibcode:1989ApJ...344..441M. doi:10.1086/167812. 
  16. ^ 16.0 16.1 Kopparapu, R. K.; Ramirez, R.; Kasting, J.F.; Eymet, V.; Robinson, T. D.; Mahadevan, S.; Terrien, R.C.; Domagal-Goldman, S.; Meadows, R.; Deshpande, V. Habitable Zones around Main-sequence Stars: New Estimates. The Astrophysical Journal. March 2013, 765 (2): 16. Bibcode:2013ApJ...765..131K. S2CID 76651902. arXiv:1301.6674  . doi:10.1088/0004-637X/765/2/131. 
  17. ^ Heinze, A. N.; et al. Constraints on Long-period Planets from an L'- and M-band Survey of Nearby Sun-like Stars: Observations. The Astrophysical Journal. May 2010, 714 (2): 1551–1569. Bibcode:2010ApJ...714.1551H. S2CID 119199321. arXiv:1003.5340  . doi:10.1088/0004-637X/714/2/1551. 
  18. ^ Cantrell, Justin R.; et al, The Solar Neighborhood XXIX: The Habitable Real Estate of Our Nearest Stellar Neighbors, The Astronomical Journal, October 2013, 146 (4): 99, Bibcode:2013AJ....146...99C, S2CID 44208180, arXiv:1307.7038  , doi:10.1088/0004-6256/146/4/99. 
  19. ^ Bill Steigerwald. "Goldilocks" Stars May Be "Just Right" for Finding Habitable Worlds. NASA. 2019-03-07 [2020-05-12]. （原始内容存档于2019-06-17）. 'I find that certain nearby K stars like 61 Cyg A/B, Epsilon Indi, Groombridge 1618, and HD 156026 may be particularly good targets for future biosignature searches,' said Arney. 

注释

外部链接

检索自“https://zh.wikipedia.org/w/index.php?title=Groombridge_1618&oldid=83166818”