Nearly 400 years after they were first sighted by Galileo through a telescope, sunspots continue to perplex scientists.
Sunspots are the precursors to solar flares and other space weather events.
If you look at the monthly values, they fluctuate wildly, as well. The sunspot number is increasing as we head toward solar maximum in mid-2000. Prior to the Space Age, the most visible effect of solar activity was the showy aurora borealis, or Northern Lights, Hathaway said. At best, their results have been mediocre. The long-term predictions, called precursor methods, only forecast a cycle's general intensity.