3. Largest Solar Flare on Record

The Sun was supposed to be well past the peak in its 11-year cycle of activity. But that didn't stop it from unleashing the most powerful radiation flare on record Nov. 4.

The historical eruption came at a time when the public and media were paying close attention to an unprecedented string of solar storms that pounded our planet's upper atmosphere and lit up the skies with aurora as far south as Texas. It was a rare and shining moment for the Sun, its fury on full display on the evening television news as officials worried about potential damage to satellites and power grids.

In the end, three huge sunspots combined to kick up an amazing string of 10 major flares in two weeks. Two Japanese satellites were knocked out, an instrument on the Mars Odyssey orbiter was lost, and the navigation system of the European Space Agency's Mars Express probe was temporarily disrupted.

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