Italian photographer Walter Benotto managed to document this rare phenomenon over the skies of northern Italy, where it appeared as a giant red ring with a diameter of 320 kilometers.
According to experts, this phenomenon is caused by powerful electromagnetic pulses emitted by thunderstorms, occurring at an altitude of approximately 100 miles above the Earth's surface. It is one of the fastest and most difficult weather phenomena to observe due to its extreme speed and short duration.
This discovery comes as part of growing scientific efforts to study rare weather phenomena in the upper atmosphere, which may contribute to a better understanding of atmospheric and energy interactions.
Benotto captured the unusual flash over the foothills of the Italian Alps from his home in the small town of Possagno on November 17. According to the National Oceanic and Atmospheric Administration (NOAA), "upper-atmospheric lightning" is a disc-shaped flash that can rapidly expand to 300 miles (480 kilometers) and lasts for less than a millisecond. This phenomenon occurs at high altitudes above thunderstorms when a powerful electromagnetic wave pulsates upward into the ionosphere, the same ionized region of Earth's upper atmosphere where the aurora borealis (northern lights) are formed.
Binotto had initially gone out in an attempt to photograph "sprites" - brief electrical discharges above thunderstorms that occur in the upper atmosphere - so he focused his camera on a thunderstorm with fewer clouds.
"I wasn't able to capture any 'sprites,' but fortunately, I was able to capture this upper atmospheric lightning," Binotto told Space.com.
Benotto added, "The upper-air lightning was generated by a powerful negative lightning strike in a storm in the Vernazza region, about 300 km south of my location." One of the lightning bolts reached an exceptional intensity of 303 kA (the negative sign indicates the polarity of the lightning, not that the current is below zero), producing a powerful electromagnetic pulse that illuminated the ionosphere.
For comparison, ordinary lightning strikes typically carry a current of only 10 to 30 kiloamperes. According to Spaceweather.com, this upper-air lightning strike reached an altitude of 160 km above the Earth's surface and spanned a diameter of 320 km.
This is not the first time Binotto has captured this strange phenomenon. He took a picture of another, even more dramatic, upper-air lightning event on March 23, 2023, also from his home in Possagno.
The image shows the structure of the phenomenon in more detail as it expands like a red halo across the sky.
