120度幻日
120度幻日是一種很少見的暈,常伴隨特別明亮的幻日出現,當時的大氣層的卷雲中會充滿冰晶。得名自現象發生時幻日周圍成對的±120°幻日環。[1]
120度幻日是光線六角形冰晶上經過至少兩次反射的產物,會在幻日環上形成明亮的藍白色光點。實際上因為會和雲相混淆,所以其可觀測到的顏色十分模糊。[2]
参考文献
- ^ 120° Parhelia. www.paraselene.de. [2009-03-08]. (原始内容存档于2011-07-19). (including a HaloSim simulation.)
- ^ Les Cowley (?). 120° Parhelia. Atmospheric Optics. [2007-04-15]. (原始内容存档于2007-04-30).
外部連結
- A photo of a 120° parhelion in the Czech Republic in October 2006(页面存档备份,存于互联网档案馆)
- A photo by Joni Tornambe, 2006(页面存档备份,存于互联网档案馆)
- A video from Russia featuring both 120° parhelia, as well as the classic sundogs and parhelic circle, 2007(页面存档备份,存于互联网档案馆)
- A similar video from Kazakhstan with very bright 120° parhelia, 2007(页面存档备份,存于互联网档案馆)