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Wednesday, March 26, 2008

"The Sun awakens in the early dawn of Sunspot Cycle 24"


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!

DX note: the forecast for March 26, 27, 28: Solar Flux expected to reach 90 to 95. This will increase higher frequency propagation on most DX paths. This is a time to be on the radio.
(c) Tomas Hood, NW7US
Contributing editor:
CQ Magazine, CQ VHF, Popular Communications

A point of clarification:

While these three sunspots "are cycle 23 spots based on their polarities", never-the-less, my bulletin does not state that these sunspots are actually cycle 24 spots. Rather, I am pointing to the new level of activity as a possible "waking up" of the sun after a long period of quiet. And, that this could signal the gradual increase of solar activity expected of a newly starting cycle.

Experts are not yet totally agreeing on the statistical end of cycle 23 - but are speculating that February 2008 was the statistical end. Whether or not these sunspots are oriented correctly to belong to a new cycle is not, in my opinion, as "important" to a radio operator as is the actual 10.7-cm flux levels, and the occurrence of space weather (flares, sunspots, and so forth). No one knows, yet, the certain end and start points. We'll know when we can look back at the data.

Anyhow - some people are purists. I'm being nudged in my discussions about the orientation of these spots. They are not reversed. So, they must not be cycle 24's. However, that was not my point, and I still hold that, in terms of the statistical end point (probably in Feb 2008), this new level is part of the sun's waking moments. Take a look at the forecasted Flux levels for the next few days. 95!!!

That's great for a radio operator on HF. Regardless of the orientation of the sunspots... And yes, we probably will see some very quiet points again. I'll venture, though, that they will be shorter and shorter as we move farther into 2008.
- NW7US, Tomas
(c) Tomas Hood, NW7US
Contributing editor:
CQ Magazine, CQ VHF, Popular Communications
(HCDX 26 March 2008)