Credit: NASA

After a prolonged lull in activity, sunspots, and their associated solar storms, are on the rise again.

According to a panel of scientists led by the US Space Weather Prediction Center, part of the National Oceanic and Atmospheric Administration, a minimum in sunspot activity was passed in December 2008. In a consensus forecast on 8 May, the researchers said a new cycle of solar storms would peak in May 2013. But judging by the historical record, the recent persistence of a quiet Sun suggests that sunspot activity at this peak will be the weakest since the solar maximum of 1928.

NASA's STEREO mission spotted large regions of magnetic activity (white spots on image) on the Sun this month.