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http://spaceweather.comsolar cycle 24 begins: solar physicists have been waiting for the appearance of a reversed-polarity sunspot to signal the start of the next solar cycle. the wait is over. yesterday, a magnetically reversed sunspot emerged at solar latitude 30 n, shown in this photo taken by greg piepol of rockville, maryland:
for reasons explained in a recent science@nasa story, this marks the beginning of solar cycle 24 and the first step toward a new solar maximum. intense solar activity won't begin right away. solar cycles usually take a few years to build from solar minimum (where we are now) to solar max (expected in 2011 or 2012). it's a slow journey, but we're on our way!
