Thunderstorms fill the sky with lights above as well as beneath the clouds. A sprite is a flash of light directly above large thunderstorms. Sprites occur a fraction of a second after strong lightning strokes, soaring upward to an altitude of nearly 100 kilometers. These transient luminous events are similar to lightning. Just as the solid earth conducts electricity and attracts lightning, so does the ionosphere, the layer above the stratosphere. A large lightning stroke launches a rising electromagnetic pulse that excites the thin air until it emits light. Sprites are very plentiful in the Midwest where great thunderstorms are common, but they are reported in many other places as well.
Over the weekend, an atmospheric scientist in Europe photographed a sprite that resembled a giant luminous squid floating over a thundercloud in France. His high resolution images can be found on this website: