elve

One of the catalogued transient luminous events (TLEs), consisting of a gigantic, toroidal-shaped luminous ring that expands at great speed in the upper atmosphere, around 100 km of altitude, reaching hundreds of kilometers in diameter. It is imperceptible to the naked eye, since its duration is less than one thousandth of a second. Like sprites, it arises above certain storms, simultaneously with positively charged cloud-to-ground lightning strokes.