Big Storm

The Sun can turn nasty. But we don’t know just how nasty it can get. Astronomers have been keeping a close eye on it with telescopes for only a couple of centuries. In the lifetime of the Sun, that’s barely the blink of an eye. So scientists are looking farther into the Sun’s past — through tree rings and layers of ice that are hundreds or thousands of years old.
The Sun turns “nasty” when it produces big explosions of energy and charged particles. They can damage orbiting satellites, interfere with aircraft schedules, and knock out power grids on the ground. The largest of these explosions yet seen came in 1859. But no one knows how much bigger such outbursts might get. And that means no one knows how to prepare for the worst the Sun can give us.
Scientists had already found evidence of two big outbursts in tree rings and ice cores — layers of ice pulled up from far beneath the surface. The biggest happened more than 1200 years ago.
A recent study found evidence of a third — about 270