Solar physicists study the sun and keep track of solar activity by monitoring sunspots. They believe the next solar maximum will occur in mid-2013. With our dependency on sun-sensitive technologies, predicting solar activity has become a high priority for scientists.
Sunspots form because of the powerful magnetic forces that exert enormous pressure and control on the sun's superhot gases. When a strong twisted magnetic field breaks the sun's surface, the area cools a few thousand degrees. That area appears darker, creating a sunspot. Even though sunspots appear dark, they are actually about 10 times brighter than the full moon. Large sunspots have two distinct parts: the inner darker core called the umbra and a large lighter surrounding region called the penumbra.
Sunspots erupt in huge explosions called solar flares. The energy released in a flare is equal to millions of hydrogen bombs. Solar flares propel streams of energy particles from the sun into space. As these particles approach Earth, many are deflected by our magnetic field, the magnetosphere. They are then channeled to the regions around Earth's north and south magnetic poles. These particles then interact with atoms of oxygen and nitrogen in the atmosphere. This causes them to glow, resulting in the dazzling display of lights called the aurora. As the gusts of solar particles change, the lights dance and sway in the sky.
Solar maximum and solar minimum are two extremes of the sun's 11-year activity cycle. At maximum, sunspots pepper the sun's surface, solar flares erupt, and the sun hurls billion-ton clouds of electrified gas toward Earth.
An increase in solar eruptions may be good for sky watchers who enjoy auroras, but not so good for astronauts and any of the billions of dollars' worth of satellites in orbit. It's also a concern for farmers, surveyors, airlines, emergency managers, financial institutions and many other businesses you deal with every day.
First Published: May 3, 2012, 4:00 a.m.
Updated: May 3, 2012, 4:31 a.m.