Iridescence from Super Moonlight

Sometimes, waking up early produces unexpected dividends. In the wee morning hours of June 24, I was able to capture the lenticular cloud iridescence shown above from the Sunriver Golf Course in St. George, Utah. Just one day past the “super moon”, moonlight illuminated this double-convex mid-level cloud (lenticularis).    Image © Ronald Smith

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Because lenticular clouds are composed of tiny water droplets, iridescence is sometimes observed about their edges. Iridescence or irisation is a diffraction phenomenon. Light, in this case moonlight, is deflected by similar-sized droplets. Minute differences in the shape or size of the droplets can result in remarkable differences in brightness and color intensity. Note the “milk dipper” of Sagittarius just below the colorful cloud.    Summary Author: Ronald Smith

source EPOD