Where Are All of the Sunspots?
July 15, 2009
The two photos above were snapped precisely four years apart and illustrate quite well the current state of the Sun. At left is a photo taken on July 5, 2005. This is an example of the robust solar activity (numerous sunspots), which is characteristic of the Sun during non-solar minimum periods. The second photo in the collage is from July 5, 2009 and is representative of the dearth of sunspots that have been reported for much of 2009. As noted by Dr. Tony Phillips (author of the SpaceWeather web page), as of March 31, there were no sunspots on 78 of the year's first 90 days. Through July 6, 77% of the days thus far this year have been sunspot free. Moreover, 2007 and 2008 were also low sunspot years. During the current solar minimum period, sunspots have been absent on 653 days. This compares with an absence of 485 days for a "normal" solar minimum. It's difficult to know with any certainty why so few sunspots have been traversing the face of Old Sol in recent months. One theory that has gained some support recently involves a conduit deep inside the Sun (approximately 4,350 miles or 7,000 km below the surface) that may be migrating much more slowly than usual. Note that on the photos the number designation refers to the particular sunspot cycle – AR 11024 is solar cycle 24.