Sun's Recent Behavior Is Odd
In very rough terms, the sun's activity ebbs and flows in an 11-year
cycle, with flares, coronal mass ejections and other energetic phenomena
peaking at what is called solar maximum and bottoming out at solar
minimum. Sunspots, markers of magnetic activity on the sun's surface,
provide a visual proxy to mark the cycle's evolution, appearing in
droves at maximum and all but disappearing at minimum.
But the behavior of our host star is not as predictable as all that --
the
most recent solar minimum was surprisingly deep and long, finally
bottoming out around late 2008 or so.
Solar physicists here at the semiannual meeting of the American
Astronomical Society this week offered a number of
mechanisms to shed light on what has been happening on the sun of late,
but
conceded that the final answer -- or more likely answers -- remains
opaque.
Beyond scientific understanding, motivations for better solar weather
forecasts include hopes to use them to safeguard against electrical grid
disruptions, damage to Earth-orbiting satellites and threats to the
health of
space travelers posed by solar radiation flare-ups.
Read more:
http://ow.ly/1R7gQ
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