sunset rises up from the ground. Therefore, at sunset on the ground, sunlight still shines on clouds above. Under usual circumstances, a pretty sunset might be visible, but unusual noctilucent clouds float so high up they can be seen well after dark. Pictured above, a network of noctilucent clouds casts a colorful but eerie glow visible above the dark. Although noctilucent clouds are thought to be composed of small ice-coated particles, much remains unknown about them.
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& Michigan Tech. U.
Based on Astronomy Picture Of the Day
Publications with keywords: Earth - atmosphere - clouds - noctilucent clouds - sunset
Publications with words: Earth - atmosphere - clouds - noctilucent clouds - sunset