Our friend Adrian Strand was able to capture these beautiful noctilucent clouds – also called night-shining clouds – on May 30, 2013 over the Solway Firth, which forms part of the border between England and Scotland. He said:
… the night sky turned electric.
These clouds can only be observed from high-latitude locations, at certain times of year, after the sun is below the horizon. The notilucent cloud season for the Northern Hemisphere typically begins around now. Adrian says these are the first he’s seen so far in 2013.
These clouds, by the way, are the highest clouds in the Earth’s atmosphere. They’re made of crystals of water ice and form the edge of polar mesopheric clouds.