According to data from Mount Wilson Observatory, more than an entire
month has passed without the Sun showing a spot. The last time such an
event occurred was in 1913 June. Sunspot data have been collected
since 1749. The event may be significant, as many climatologists now
believe that solar magnetic activity -- which affects the number of
sunspots -- influences climate on the Earth.
When the Sun is active, it is not uncommon for sunspot numbers to be
100 or more in a single month. Every 11 years, activity slows, and
numbers briefly drop nearly to zero. Normally sunspots return very
quickly, as a new cycle begins. But this year -- which corresponds to
the start of Solar Cycle 24 -- the minimum has been extraordinarily
long and quiet, with the first seven months averaging a sunspot number
of only 3, August following with none at all. In the past 1000 years,
three previous such events (necessarily inferred from data more
oblique than actual sunspot counts) -- the Dalton, Maunder and Spörer
Minima -- have all been associated with rapid cooling, in one case
enough to be called a 'mini ice age'.
Uh oh...
--
simon
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