UK | Freak solar flares that may destroy us all | ECHOES project

Twice in the last 1,500 years, the sun released blasts of energy no scientist ever thought possible. If that happens again, none of our satellites will survive. On the upside, scientists can use these freak solar flares to solve archaeological riddles, says Michael Dee.

It must have been an awesome sight, back in the year 775. Northern lights were visible all over the globe, from Hawaii to Japan and from Tasmania to Greenland. Maybe the night sky lit up as if a giant had switched on some huge spotlights. Maybe it turned blood red. Nobody really knows. What we do know is that something huge happened. A blast of energy hit the earth and caused neutrons to collide with nitrogen particles present in the atmosphere, creating an extra heavy form of carbon we know as 14C, or radiocarbon. This particular year, the 14C levels spiked eight times higher than usual. Two hundred years later, in 994, it happened again. Once again, it led to a jump in 14C levels. But nobody knows what caused it. And nobody knows if it will happen again, or when.