This is an upper atmosphere electrical discharge called a sprite. The photo was taken over the U.S. by scientist Jason Ahrns recently while aboard the National Center for Atmospheric Research’s Gulfstream V research aircraft. (Photo: Jason Ahrns/Flickr)


They were so mysterious that for many years pilots who saw them while flying above thunderstorms refused to tell anyone for fear of being thought a wacko.

And while the upper atmosphere flash and spark of red and blue "lightning" or "sprites" – something like a negative image of lightning – have been understood since the late 1980s, capturing them in photos is still rare.

This week, however, a series of photos and videos of the sprites have been published by scientist Jason Ahrns. He took the images while aboard the National Center for Atmospheric Research’s Gulfstream V research aircraft.

Ahrns explained the phenomenon and how he captured them in an email exchange:

"A sprite is a kind of upper atmosphere electrical discharge associated with thunderstorms. A large electric field, generated by some lightning strokes, ionizes the air high above the cloud, which then emits the light we see in the pictures. They're associated with positive lightning strokes, which is when the cloud has a buildup of positive charge and releases a bolt of lightning.


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