June
17, 2009: The
sun is in the pits of a century-class solar minimum, and sunspots
have been puzzlingly scarce for more than two years. Now,
for the first time, solar physicists might understand why.
At
an American Astronomical Society press conference today in
Boulder, Colorado, researchers announced that a jet stream
deep inside the sun is migrating slower than usual through
the star's interior, giving rise to the current lack of sunspots.
Howe
and Hill found that the stream associated with the next solar
cycle has moved sluggishly, taking three years to cover a
10 degree range in latitude compared to only two years for
the previous solar cycle.
The
jet stream is now, finally, reaching the critical latitude,
heralding a return of solar activity in the months and years
ahead.
Continued
tracking and study of solar jet streams could help researchers
do something unprecedented--accurately predict the unfolding
of future solar cycles. Stay tuned for that!
clipped from: science.nasa.gov 