"Like Earth, the Sun has magnetic poles,"
Kosovichev said, "but
unlike Earth, the Sun's polarity is not constant. It
changes every 11 years from magnetic north to magnetic
south and back. However, the origin of these periodic
reversals is unknown."
Earlier studies showed that polarity reversal occurs
at the middle of the 11-year cycle -- a period known
as the "solar maximum," when the number of
sunspots are at their peak. Scientists believe that
sunspots -- which are often accompanied by solar flares
and explosions -- result when pent-up magnetic fields
generated in the dynamo finally break through the surface.
According to satellite data, the giant loops observed
in the study only formed connections between magnetic
poles and trailing spots located in the same hemisphere.
"These loops never crossed the equator,"
Scherrer said.
Because the magnetic pole and the trailing spot
carried opposite magnetic polarities, each loop generated
an incredibly intense flow of electricity. As the 2000
solar maximum approached, the number of trailing sunspots
and loops increased -- creating numerous magnetic links
that may have been strong enough to contribute to the
magnetic pole reversal.
"We believe these direct magnetic links can accelerate
the process of the polar field reversal and create the
starting conditions for the next solar cycle, "
Kosovichev explained.
Next reversal in 2012!
The next solar maximum with a new polar field reversal
is expected for late 2012
- the same time as the Maya predict a giant reversal!
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