The scientists who study the Sun have not been seeing spots in front of their eyes recently. It has nothing to do with their eyes, though. Instead, the Sun itself has been spot-free for most of the year.
This year is the "solar minimum" -- the least-active time in the Sun's 11-year magnetic cycle.
At the cycle's peak, dozens of dark sunspots at a time can break out on the Sun. The spots are magnetic storms that are cooler than the surrounding gas. Many of them grow bigger than Earth, and last for days or weeks. And they're often accompanied by powerful explosions known as solar flares.
The last peak in the cycle came in 2001. Even between the peaks, though, it's not unusual to see sunspots. But this year has been the quietest in more than half a century. By year's end, the Sun could rack up close to 300 spot-free days.
That doesn't mean there's anything wrong with the Sun. The level of magnetic activity varies quite a bit from cycle to cycle. But if the Sun were to stay relatively spot-free for a long time, it could have an impact on Earth's climate. During a several-decades span in the 17th and 18th centuries, Sun-watchers saw very few sunspots, and Earth experienced some of the coldest weather on record.
There's no indication that the current quiet spell will last anywhere near that long, though. Scientists expect to see a lot more spots before their eyes as the Sun builds toward the next "solar maximum" in 2012.
Script by Damond Benningfield, Copyright 2008
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