Solar Flare 2011: Biggest Sun Storm in Four Years Passes Earth

NASA says atmosphere protects us, but satellites and electronics affected.

ByABC News
February 17, 2011, 1:15 PM

Feb. 17, 2011— -- The sun is alive. And sometimes it gets angry.

A giant solar flare -- the biggest in four years -- leapt from the face of the sun on Monday, said NASA, and sent masses of charged particles outward into space, including toward Earth.

The radiation from Monday's flare, known as a Coronal Mass Ejection, should pass the Earth today, Friday and Saturday. The charged particles will speed by at some 560 miles per second.

Do not be afraid. NOAA's Space Weather Prediction Center in Boulder, Colo., says the Earth is well-protected by its atmosphere and magnetic field. When solar radiation picks up, the most dramatic effect is usually a brightening of the aurora borealis, the famous northern lights in the sky over Arctic regions. After a big flare they are sometimes visible in the northernmost of the 48 contiguous states.

What makes this storm interesting, said Joe Kunches of the Space Weather Prediction Center, is that there were actually three flares in succession -- and radiation from the last and biggest of them is travelling faster than the particles from the first two.

"What's the effect of the triple punch?" said Kunches. "Stay tuned."

Outbursts such as the current one are actually quite common, scientists say. But modern technology can be sensitive to solar storms; scientists say satellites, power grids and communications networks can suffer outages.

"Each time we use a cell phone or pager, check a GPS locator, turn on a light, or take an over-the-pole flight, space weather could have an effect," said Jack Hayes, director of NOAA's National Weather Service, in a press statement. The Space Weather Prediction Center is part of his operation.