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During the data taking period, the sun's solar cycle will
be at its maximum, a solar maximum. What does that mean?
It is a time when the sun's magnetic dynamo flips over. As
a result, the magnetic domains on and above the solar surface
are not well ordered, causing a lot of turbulence in the particles
that are emitted by the sun. During this time, a solar storm
may couple to the Earth's magnetic field and cause problems
with satellites or electric transmission lines. It also causes
the eerie aurorae (northern or southern lights) in the sky
at high latitudes. Solar maxima generally occur about every
11 years.
Why the sun's dynamo reverses is not well understood. It
is also not well understood why there have been times of very
weak solar activity, such as during the 1600s. For Genesis,
flying during solar maximum means we will probably collect
more of the exotic types of solar wind. We will probably have
more coronal mass ejections, which are magnetically confined
bubbles of material lifting off from the surface. Other missions
have provided beautiful picture sequences of these bubbles
expanding. Another type of solar wind we expect to see more
of is coronal hole wind. During periods of low solar activity,
a very fast type of solar wind flows from relatively stationary
"coronal holes" over the north and south poles of the sun.
During solar maximum, smaller coronal holes occur at various
latitudes of the sun, and so it is encountered more often
by satellites near Earth, like Genesis. This is a boon for
us. The Genesis science team is most interested in this coronal
hole wind because it is thought to be the closest to the actual
solar composition.
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