"The ELVE was generated by intense lightning in a storm near Ancona about 285 km south of me," says Binotto. One bolt was so strong, it generated an intense electromagnetic pulse (EMP). The red ring marks the spot where the EMP hit Earth's ionosphere. Normal lightning bolts carry 10 to 30 kilo-ampères of current; this bolt was about 10 times stronger than normal.
Binotto created a graphic showing the scale of the ELVE:
ELVE season is just getting started in Europe and North America, where spring and summer thunderstorms will multiply in the months ahead. Photographers should be alert for red rings and many other things above the cloudtops. Look here.