彩色气辉带环绕银河系
(原标题: Colorful Airglow Bands Surround Milky Way)
2022-03-13
浏览次数: 22
为什么天空会像一个巨大的重复彩虹一样发光？大气光。现在空气一直在发光，但通常很难看到。然而，像即将来临的风暴这样的扰动可能会在地球大气层中引起明显的涟漪。这些重力波是空气中的振荡，类似于将岩石扔进平静的水中所产生的振荡。红色气辉可能来自87公里高的OH分子，受到太阳紫外线的激发，而橙色和绿色气辉可能是由稍高的钠原子和氧原子引起的。几年前，在中国青海普罗旺斯的克鲁克湖附近开车时，摄影师最初注意到的主要是令人印象深刻的银河系中央带。停下来拍照，令人惊讶的是，由此产生的敏感相机图像显示气辉带相当突出，横跨整个天空。特色图像经过数字增强，使色彩更加鲜艳。
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Why would the sky glow like a giant repeating rainbow? Airglow. Now air glows all of the time, but it is usually hard to see. A disturbance however -- like an approaching storm -- may cause noticeable rippling in the Earth's atmosphere. These gravity waves are oscillations in air analogous to those created when a rock is thrown in calm water. Red airglow likely originates from OH molecules about 87-kilometers high, excited by ultraviolet light from the Sun, while orange and green airglow is likely caused by sodium and oxygen atoms slightly higher up. While driving near Keluke Lake in Qinghai Provence in China a few years ago, the photographer originally noticed mainly the impressive central band of the Milky Way Galaxy. Stopping to photograph it, surprisingly, the resulting sensitive camera image showed airglow bands to be quite prominent and span the entire sky. The featured image has been digitally enhanced to make the colors more vibrant.
© Xiaohan Wang