Solar forecasters predicted 2006 would be solar minimum — that period of diminished activity on the surface of the sun.  Based upon only three satellite-based observations of solar cycles, physicists expected 2005 to be the eve of solar minimum and, therefore, a quiet year.

It has been anything but.

Between September 7th and today, a lone sunspot has exploded nine times, producing multiple solar flares and CMEs.  One recent CME, in fact, was so powerful that it generated auroras (northern lights) as far south as Arizona.  And that's just in the last week.

2005 has actually been quite active, and scientists are now admitting that they may well have prematurely attempted to forecast the solar cycle given such limited data.  Even with declining solar activity since 2000, a seeming precursor to solar minimum, physicists see this year's spike in activity as a clear indication that they do not clearly or fully understand the sun's 11-year activity cycle.

You can see more information over at NASA's site.