• Polar Stratospheric Clouds

    7 days ago - By Gurney Journey

    Polar stratospheric clouds appear high in the sky in the polar regions in winter. Photos in Iceland. Photos by h0rdur c/o Fabulous Weird
    They are composed of ice crystals and supercooled water droplets, sometimes mixed with nitric acid.
    Wikipedia says : "Particles within the optically thin clouds cause colored interference fringes by diffraction."
    The visibility of the colors may be enhanced with a polarising filter ."--
    Thanks, Atlas Obscura and Fabulous Weird
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