jet bleu

OBS: Phénomène atmosphérique encore méconnu. Flashes fugaces rougeoyants,farfadets rouges ou bleutés qui prennent naissance, lors de puissants orages, au sommet des cumulo-nimbus, et se projettent en quelques millisecondes jusqu'à des altitudes pouvant atteindre 95 kilomètres. Ces éclairs s'accompagnent de phénomènes électromagnétiques intenses, notamment des bouffées de rayonnement gamma.

CONT: Recently two new types of lightning have been verified: red sprites and blue jets. These atmospheric discharges occur very high in the Earth's atmosphere - much higher than the familiar form of lightning. Blue jets appear blue in color and go from the tops of clouds to a height of about 50 kilometers. Because blue jets typically last almost a full second, one can easily see the jet rise from the clouds with a fast video camera. Blue jets appear as narrow cones and travel about 100 kilometers per second. The existence of blue jets has been suggested previously, but only in 1994 were aircraft flown above massive thunderstorms with the high speed video equipment necessary to verify these spectacular events.