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Bulletin from Tomas Hood, NW7US:
"The Sun awakens in the early dawn of Sunspot Cycle 24"
During the week of March 24, the Sun became quite active. This, after
many months of long stretches of quiet, sunspot-less days. March 25
images of the sun revealed a train of sunspots, NOAA AR 0987 (a beta
configuration), 0988 (a beta configuration), and 0989 (an alpha
configuration). For many months prior, there would be an occasional
sunspot, if any at all. These three sunspots indicate a sun that is
waking up; there was even a strong M1-class solar flare on March 25,
the first such strong flare in a long period of quiet (the last such
flare was mid-2007).
The M1.7 magnitude flare originated in sunspot 0989, which was on the
very edge of the sun, not facing us. As this sunspot group rotates
into what is known as "geo-effective" position, it may well cause
intense radio blackouts and storms, while also strengthening the
ionosphere, in turn creating great DX opportunities on higher HF
frequencies during non-radio blackout periods. Radio blackouts occur
during solar flares.
On the same day, March 25, the solar flux (10.7-cm flux index) rose
from the low 70's to the high of 89 (as of the time this is being
written), and the flare caused minor storming and a radio blackout on
HF. This is a great trend for those interested in using the high
frequencies for radio communications. As we now move away from
sunspot cycle minimum to the peak of cycle 24, sometime in the next
three to five years, activity will increase. With this increase in
activity will come better HF propagation on the higher portions of HF,
while also bringing an increase in radio blackouts and geomagnetic
storminess that is part of an active cycle.
We're in for the exciting start of a new solar cycle! Some
forecasters speculate that this solar cycle will not be too active. I
still hold to one early forecast that speculates that the cycle may be
a very active and exciting one. Time will tell!
(c) Tomas Hood, NW7US
Contributing editor:
CQ Magazine, CQ VHF, Popular Communications
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