蝎虎座EV

蝎虎座EV（也稱為格利澤873、HIP 112460）是蝎虎座中一颗暗淡的紅矮星，距離太陽大約16.5光年。它是在那個天區中距離太陽最近的恆星，但它的視星等只有10等，勉強可以使用雙筒望遠鏡觀看。蝎虎座EV是一颗光譜類型為M3.5的焰星，會釋放出X射線。 在2008年4月25日，美國國家航空暨太空總署的尼爾·格雷爾斯雨燕天文台觀測到來自蝎虎座EV的一次創紀錄閃焰爆發。這個閃焰的威力比曾經觀測到最強的太陽閃焰還要大數千倍。不過蝎虎座EV離地球比太陽遠很多，因此看起來不如太陽閃焰那麼明亮。如果當時的蝎虎座是出現在夜空中，這次的閃焰爆發就能用肉眼直接看到。這是除了太陽之外，在恆星上所見到最明亮的閃焰事件。 蝎虎座EV是比我們的太陽年輕許多的恆星，估計僅有3億歲，並且仍然在高速自轉。快速自轉，加上內部的對流，產生一個比太陽強很多的磁場。這種強磁場被認為對恆星產生如此明亮的閃焰，有著一定的作用。在閃焰爆發之後，恆星呈現藍色 。 Perryman, M. A. C.; et al. The HIPPARCOS Catalogue. Astronomy & Astrophysics. April 1997, 323: L49–L52. Bibcode:1997A&A...323L..49P.  V* EV Lac -- Flare Star. SIMBAD. Centre de Données astronomiques de Strasbourg. [2010-06-12]. （原始内容存档于2017-11-07）.  Montes, D.; López-Santiago, J.; Gálvez, M. C.; Fernández-Figueroa, M. J.; De Castro, E.; Cornide, M. Late-type members of young stellar kinematic groups - I. Single stars. Monthly Notices of the Royal Astronomical Society. November 2001, 328 (1): 45–63. Bibcode:2001MNRAS.328...45M. S2CID 55727428. arXiv:astro-ph/0106537 . doi:10.1046/j.1365-8711.2001.04781.x.  Erro, B. I. Infrared photometry of UV CET stars. Boletin del Instituto de Tonantzintla. 1971, 6: 143. Bibcode:1971BITon...6..143E.  Wilson, Ralph Elmer. General Catalogue of Stellar Radial Velocities. Carnegie Institute Washington D.C. Publication (Washington: Carnegie Institution of Washington). 1953. Bibcode:1953GCRV..C......0W.  Gatewood, George; de Jonge, Kiewiet Joost; Stephenson, Bruce. One-milliarsecond precision parallax studies in the regions of Delta Cephei and EV Lacertae. Publications of the Astronomical Society of the Pacific. 1993, 105 (692): 1101–1106. Bibcode:1993PASP..105.1101G. doi:10.1086/133287.  Phan-Bao, Ngoc; Martín, Eduardo L.; Donati, Jean-François; Lim, Jeremy. Magnetic Fields in M Dwarfs: Rapid Magnetic Field Variability in EV Lacertae. The Astrophysical Journal. July 2006, 646 (1): L73–L76. Bibcode:2006ApJ...646L..73P. S2CID 18410819. arXiv:astro-ph/0603480 . doi:10.1086/506591.  Rojas-Ayala, Bárbara; et al. Metallicity and Temperature Indicators in M Dwarf K-band Spectra: Testing New and Updated Calibrations with Observations of 133 Solar Neighborhood M Dwarfs (PDF). The Astrophysical Journal. April 2012, 748 (2): 93 [2019-09-21]. Bibcode:2012ApJ...748...93R. S2CID 41902340. arXiv:1112.4567 . doi:10.1088/0004-637X/748/2/93. （原始内容存档 (PDF)于2021-01-29）.  Testa, Paola; Drake, Jeremy J.; Peres, Giovanni. The Density of Coronal Plasma in Active Stellar Coronae. The Astrophysical Journal. December 2004, 617 (1): 508–530. Bibcode:2004ApJ...617..508T. S2CID 17532089. arXiv:astro-ph/0405019 . doi:10.1086/422355.  Schmitt JHMM; Fleming TA; Giampapa MS. The X-ray view of the low-mass stars in the solar neighborhood. Astrophys. J. Sep 1995, 450 (9): 392–400. Bibcode:1995ApJ...450..392S. doi:10.1086/176149.  Abdul-Aziz, H.; Abranin, E. P.; Alekseev, I. Yu; Avgoloupis, S.; Bazelyan, L. L.; Beskin, G. M.; Brazhenko, A. I.; Chalenko, N. N.; Cutispoto, G.; Fuensalida, J. J.; Gershberg, R. E.; Kidger, M. R.; Leto, G.; Malkov, Yu. F.; Mavridis, L. N.; Pagano, I.; Panferova, I. P.; Rodono, M.; Seiradakis, J. H.; Sergeev, S. G.; Spencer, R. E.; Shakhovskaya, N. I.; Shakhovskoy, D. N. Coordinated observations of the red dwarf flare star EV Lacertae in 1992. Astronomy and Astrophysics Supplement Series. December 1995, 114: 509–526 [14 January 2022]. （原始内容存档于2022-12-20）.  Dunbar, Brian. Smith, Yvette , 编. Pipsqueak Star Unleashes Monster Flare. NASA. May 20, 2008 [2010-06-12]. （原始内容存档于2016-03-15）.  https://m.youtube.com/watch?v=rqsckfsXU8U