Mixed-Up Sun

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The Sun has been a little confused this year. In January, scientists reported that it had started a new 11-year magnetic cycle. The evidence was a sunspot that had reversed polarity from those seen in the previous cycle. In other words, its north and south magnetic poles were the opposite of those of earlier sunspots.

But a couple of months later, three new sunspots broke out, and they had the same magnetic alignment as those of the previous cycle.

Fortunately, nothing was amiss. The Sun's overall level of magnetic activity was just so low that there was no strong preference for either alignment.

As the Sun rotates on its axis, different layers of hot gas spin at different rates. That generates a powerful magnetic field. Every 11 years, the field grows strongest and most tangled. That creates more sunspots, which are relatively cool, dark magnetic blemishes on the Sun's surface. It also creates big explosions of radiation, plus "burps" of charged particles. These outbursts can have a big impact on satellites, radio, air travel, and other aspects of our technology.

Between the "peaks" of the magnetic cycle, the Sun grows quiet. There are few sunspots -- and sometimes none at all. We're in one of those "solar minimums" right now. But over the next few years, the level of magnetic activity will increase. The old solar cycle will fade away, while the new one ramps up toward the next peak -- around 2012.

Script by Damond Benningfield, Copyright 2008

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