<ul><li>Photographer Aaron Watson captured extraordinary green ripples of airglow in the night sky above Colorado on May 26.</li><li>These ripples, created by chemiluminescence in Earth's upper atmosphere, were visible in Watson's timelapse but mostly invisible to the naked eye.</li><li>The airglow was caused by oxygen atoms releasing stored energy as light, resulting in a mesmerizing green glow.</li><li>The wave-like patterns in the sky were formed by nearby thunderstorms creating gravity waves in the upper atmosphere.</li></ul>

Photographer captures ghostly ripples over Colorado night sky. 'It is rare to see it directly overhead and moving like that'

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