Scientists studying sunspots for the past two decades have concluded that the magnetic field that triggers their formation has been steadily declining. If the current trend continues, by 2016 the sun's face may become spotless and remain that way for decades—a phenomenon that in the 17th century coincided with a prolonged period of cooling on Earth.

The last solar minimum should have ended last year, but something unexpected has been happening. Although solar minimums normally last about 16 months, the current one has stretched over 26 months—the longest in a century. A reason, according to one source may be that the magnetic field strength of sunspots appears to be waning.

Tracking and predicting solar minimums and maximums is growing in importance given the potential for devastating solar flares.