Massive Solar Flare Could Have Caused 8th Century Radiation Burst

A mysterious spike in atmospheric carbon-14 levels 12 centuries ago might be a sign the Sun is capable of producing solar storms dozens of times worse than anything we’ve ever seen, a team of physicists calculates in a paper published in Nature.

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If the 774-775 event was indeed a flare, it’s a disturbing find. Such a flare would be about 60 times more powerful than the 1989 solar storm that knocked out power to much of Quebec for nine hours on a cold winter night. Multiply that by 60, and add two decades of increased technological vulnerability, and the effects might be disastrous. “A lot of people could die,” Melott says. “You could have power out for months or longer — no refrigerated food, no food being transported to all the people who live in big cities.”
[link to blogs.nature.com]