当彩虹微笑
(原标题: When Rainbows Smile)
2022-03-11
浏览次数: 26
想看到彩虹般的微笑吗？当太阳低垂的时候，看看天顶附近（向上），你就会明白了。这是2月24日在西西里岛拉古萨的一棵棕榈树顶上拍摄的冰晕的例子，被称为环天顶弧。这些色彩鲜艳的弧线因其倒置的曲率和颜色而被称为微笑彩虹。对于环天顶弧，天顶在中心，红色在外面，相比之下，彩虹的弧线在倾盆大雨后向地平线弯曲。然而，真正的彩虹是由水滴折射阳光形成的，从而产生了一系列的颜色。环天顶弧是平面六边形冰晶折射和反射的产物，就像在高空薄云中形成的形成太阳的冰晶一样。
查看原文解释
Want to see a rainbow smile? Look near the zenith (straight up) when the sun is low in the sky and you might. This example of an ice halo known as a circumzenithal arc was captured above a palm tree top from Ragusa, Sicily on February 24. The vividly colorful arcs are often called smiling rainbows because of their upside down curvature and colors. For circumzenithal arcs the zenith is at the center and red is on the outside, compared to rainbows whose arcs bend toward the horizon after a downpour. True rainbows are formed by water droplets refracting the sunlight to produce a spectrum of colors, though. Circumzenithal arcs are the product of refraction and reflection in flat hexagonal ice crystals, like the ice crystals that create sundogs, formed in high thin clouds.
© Marcella Giulia Pace