Lightning between Earth and Space; August 1997; Scientific American Magazine; by Mende, Sentman, Wescott; 4 Page(s)

Since ancient times, lightning has both awed and fascinated people with its splendor and might. The early Greeks, for instance, associated the lightning bolt with Zeus, their most powerful god. And even after a modern understanding of the electrical nature of lightning developed, certain mysteries persisted. Many observers described luminous displays flickering through the upper reaches of the night sky. Some of these curiosities could be explained as auroras or weirdly illuminated clouds, but others were more baffling. In particular, pilots flying through the darkness occasionally observed strange flashes above thunderstorms. But the scientific community largely regarded these reports as apocryphal--until 1990, when John R. Winckler and his colleagues at the University of Minnesota first captured one of these enigmatic phantoms using a video camera. Their images revealed lightning of a completely new configuration.

Winckler¿s achievement ushered in a flurry of activity to document such highaltitude electrical phenomena. And hundreds of similar observations--from the space shuttle, from aircraft and from the ground--have since followed. The result has been a growing appreciation that lightninglike effects are not at all restricted to the lower atmospheric layers sandwiched between storm clouds and the ground. Indeed, scientists now realize that electrical discharges take place regularly in the rarefied air up to 90 kilometers above thunderclouds.