The Biggest Storm You Won't See

On Monday night, while most of us were snug in our beds, our sun unleashed an X2 solar flare, the biggest flare since December 5, 2006.

Solar flares come in three classes, according to their x-ray brightness. X-class flares are big, real big. These are major events than can trigger planet-wide radio blackouts and long-lasting radiation storms. The 2006 flare was an X9, practically an explosion on the surface of the sun. Back in 2005, Old Sol let off an X17! But even a small flare can zap a satellite, turning it into a "zombiesat,"as happened to Galaxy 15 last year.

Monday's flare sent a cloud of energetic particles toward Earth that will impact our atmosphere over the next 48 hours. The highest period of activity is tomorrow, February 18th. The Space Weather Forecast (and yes, there is such a thing) predicts that today will be fairly quiet, with "an increase to unsettled to active conditions" on Friday.

Observers at high altitudes, for example up in our mountains, might get to see some auroral activity, and shortwave radio communications could be affected. Southern China experienced some shortwave interruptions on February 15th, as the China Meteorological Administration (CMA) reported yesterday.

Don't bother with an umbrella, but a tinfoil hat might not be out of place. (Kidding!)