Posted by BC on September 14th, 2009
Sunspots are caused by magnetism. When the magnetic fields are strong (1500 gauss or stronger), sunspots form. If the field is not as strong, then no spot.
The current trend on sunspot magnetism is on the downhill side. Matt Penn of the National Solar Observatory in Tucson, Arizona, said that if the trend continues, we will see the end of sunspots in 2015. The loss of magntic energy to cause sunspots has been declining at a rate of 50 gauss a year for the past 17 years.
Other scientists believe that the sunspots will be back. The 70-year Maunder Minimum in the 17th Century is a good example of a long spotless spell. We saw many sunspots after the Minimum was over. This may just be one of our Sun’s natural events.
More information on the vanishing sunspots.Note: Although sunspots have been few, prominences are looking good. Spaceweather.com has some nice photos listed.