for National Geographic News Cloud-to-Earth lightning bolts are
a well-known natural electrical occurrence. Now scientists have
discovered and photographed for the first time enormous,
90-kilometer-high (55-mile), luminous, electric discharges that
deliver large quantities of current from thunderstorms to the
edges of the Earth's atmosphere. The flashes, described in a
letter published in the current issue of the journal Nature, is
believed to be a type of phenomenon known by atmospheric
physicists as a "transient luminous event." Though other
transient luminous events, known as sprites and blue jets, have
been the subject of intense study since the first was
photographed accidentally about 14 years ago, nothing quite so
large has been observed before. "It is likely that these
gigantic jets are a special feature of oceanic thunderstorms,"
says the letter that describes the flashes detected above a
thunderstorm in the South China Sea last year. The enormous jets
may play an important role in the global electri