RARE STRATOSPHERIC CLOUDS: Around the Arctic Circle, sky watchers are reporting rare clouds nearly as colorful as the Northern Lights. Floating through the stratosphere, where clouds do not belong, their icy forms are visible even after sunset. These clouds can only form when the Arctic stratosphere is exceedingly cold. Visit today's edition of Spaceweather.com for photos and more information.
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Above: Polar stratospheric clouds over Stockholm, Sweden, on Dec. 2, 2019. Photo credit: Peter Rosén. Browse the photo gallery for more.
