A giant, circular halo of red light that looked like it came straight out of a fantasy alien movie appeared and disappeared in milliseconds, meaning most people are probably missing this bizarre image. But one man, nature photographer Walter Binotto, managed to take a picture of the sky Above the town of Possagno in northern Italy.

What was that

The red ring wasn’t actually over the city. Instead, a gigantic circle about 360 kilometers in diameter trembled over central Italy and parts of the Adriatic Sea. It was just the perspective that made the ring look like it was hanging over the city.

This is known as the epidemic “light emission and very low frequency disturbances from electromagnetic pulse sources”or ELVE for short. ELVEs are a rare type of stratospheric/mesospheric intense storm electrification (SPRITE) disturbance. Red rings are formed when electromagnetic pulses (EMI) emitted by lightning strike Earth’s ionosphere, the ionized portion of the upper atmosphere that extends 80 to 644 kilometers above the ground.

Map of Italy with the ring on it / Photograph: Valter Binotto

Binotto believes that ELVE was created by EMI produced by a major storm near Ancona., a town located about 280 kilometers southeast of Possagno. Normally, lightning does not emit EMI because it does not carry enough current. But during this storm, extremely powerful lightning, at least 10 times stronger than normal lightning, likely produced an electric shock wave that then struck the ionosphere. When electrons from inside the EMI enter the ionosphere, the charged particles activate nitrogen atoms, which then emit a reddish glow.