sprite

The name of the best-known and most photographed transient luminous event (TLE) of all those catalogued to date. This elusive luminous phenomenon, of an electrical nature, occurs in the upper atmosphere. It sometimes arises above storms, as a consequence of the sudden changes in the electric field generated by certain lightning strokes, preferentially of positive charge. Its appearance is reminiscent of a jellyfish or fireworks, with a diffuse upper part, of reddish colors, located around 80 kilometers of altitude - in the upper mesosphere -, and a lower part made up of a series of filaments of very ionized air, each between 10 and 100 meters thick, known as streamers (streamers), which display a bluish tint. In its upper part, the ionization of the air is greater, which prevents the formation of those filaments, generating a diffuse discharge, known as a halo sprite, that can reach several hundred kilometers in width. The duration of a typical sprite is a few hundredths of a second, although the fastest last only a few milliseconds. The glow generated by the halo sprite is the most fleeting luminous manifestation, since it barely lasts between 1 and 2 milliseconds.