"In the past decade, high-speed, light-sensitive cameras have allowed scientists to describe a menagerie of electrical phenomena, which bear names that would be more at home in a Tolkien novel than a physics textbook. Sprites, blue jets and associated flashes called elves, crawlers, trolls and pixies are all fleeting electrical discharges that accompany thunderstorms.

All these phenomena are hard to spot, as they last for less than a blink of an eye and are obscured from below by cloud. They can be glimpsed along storm fronts and from aeroplanes flying above the clouds." "Video images captured in Puerto Rico suggest that blue flashes of light, much like lightning, feed energy from thunderstorms up into the Earth's ionosphere - a blanket of electrically charged air some 70 kilometres above the ground."

The event "was detected on 24 video frames, each lasting 33 milliseconds each" - reports at BBC and Nature.com