彗翎
外观
![](http://upload.wikimedia.org/wikipedia/commons/thumb/b/be/Comet_Parts.jpg/200px-Comet_Parts.jpg)
![](http://upload.wikimedia.org/wikipedia/commons/thumb/2/2f/C2007N3Lulin2panel_brimacombe.jpg/250px-C2007N3Lulin2panel_brimacombe.jpg)
![](http://upload.wikimedia.org/wikipedia/commons/thumb/c/c3/Anti-tail.jpg/250px-Anti-tail.jpg)
彗翎(也稱逆向彗尾或反尾)是從彗星的彗髮投射出來的明顯的尖峰,它似乎朝向太陽,因此在幾何上與另一個彗尾相反:離子尾和塵埃尾。然而,這種現象是從地球上看到的視錯覺。彗翎是由更大的塵埃顆粒組成,它們受太陽輻射壓力的影響較小,並傾向於大致保持在彗星的軌道平面內,最終由於顆粒從彗星表面噴出的速度而沿彗星軌道形成盤狀。當地球穿過彗星的軌道平面時,是由側面看見這一盤面,並表現為特徵性的尖峰[1]。儘管盤的另一面往往會消失在塵埃的尾部,但有時仍可以看到。因此,通常只有當地球穿過彗星的軌道平面時,才能在短時間內看到彗翎[2][3]。
大多數彗星都沒有發育到足以看到彗翎的程度,但值得注意的是,確實顯示出彗翎的彗星包括1957年的阿蘭德-羅蘭彗星、1973年的柯侯德彗星[4]、1997年的海爾·波普彗星、和2013年的泛星彗星。
相關條目
[编辑]註解
[编辑]- ^ Encyclopedia of science:antitail.[失效連結]
- ^ Rao, Joe. Newfound Comet Lulin to Grace Night Skies. SPACE.com. 6 February 2009 [2009-02-25]. (原始内容存档于26 February 2009).
- ^ Tosar, Borja; Paolo Candy. What is an antitail. 3.bp.blogspot. [2009-02-25]. (原始内容存档于25 February 2009).
- ^ Naugles, John E. Statement of John E. Naugle, Associate Administrator for Space Science, NASA: Comet Kohoutek Program. Committee on Science and Astronautics U.S. House of Representatives. Hearings Before the Subcommittee on Space Science and Applications (Washington DC). 7 March 1974, 25 (3): 401 [2021-11-10].
[drawing on page 403] the Skylab crewmen observed a brilliant spike or anti tail projecting toward the Sun from the head of Kohoutek [...] Dr Zdenek Sekanina concluded that the spike was not wholly due to a perspective or geometrical effect as has been assumed in previous comet studies.
外部連結
[编辑]- Emily Lakdawalla. Got binoculars? Spot a comet near Saturn tonight. 2009-02-23 [2023-01-27]. (原始内容存档于2014-04-22).
- Online Encyclopedia of Science - Antitail (页面存档备份,存于互联网档案馆)
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