More than 14 thousand years ago, there was a solar storm so big, trees still remember it. Dwarfing modern solar storms, the event would devastate technology if it happened again today. Spoiler alert: It could.

The record-strong storm is described by a paper in the upcoming July 2025 edition of the peer-reviewed journal Earth and Planetary Science Letters. It occured in 12,350 BC and is classified as a "Miyake Event."

Miyake Events are solar storms that make the Carrington Event of 1859 look puny. Trees "remember" them in their rings, which store the carbon-14 created by gargantuan storms. At least six Miyake Events have been discovered and confirmed since Fusa Miyake found the first one in 2012. The list so far includes 664-663 BC, 774 AD, 993 AD, 5259 BC, 7176 BC, and 12,350 BC.

The Miyake Event of 12,350 BC is especially intriguing. It appears as a carbon-14 spike in Scots Pine trees along the banks of the Drouzet river in France, with a matching beryllium-10 spike in Greenland ice cores. The event was global and, based on the size of the spikes, very big.