This is a rare phenomenon known as cloud iridescence.

Add Yahoo as a preferred source to see more of our stories on Google. Noctilucent clouds glow above the horizon after sunset. The rare clouds form nearly 50 miles above Earth's surface in the ...

THE blue color of the sky on a clear day is familiar to all. And yet how many have considered the source of this delicate mantle of azure which Nature spreads over the dome of the heavens? The ...

Forming 50 miles above Earth's surface, noctilucent clouds offer a rare glimpse into one of the least-understood layers of the atmosphere. Noctilucent clouds glow above the horizon after sunset. The ...