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The K7RA Solar Update


A steady stream of sunspot activity continues to dot the Sun. We had just one day with a daily sunspot number of 0 this week -- January 19 (Tuesday) when sunspot group 1040 moved over the horizon. But the next day, old sunspot group 1039 re-emerged as 1041, and it now graces the Sun's southeast (lower left, relative to our view from Earth) quadrant. In fact, now that we have a view of most of the Sun (87.35 percent -- as of 2359 UTC today -- because of advanced orbiting instruments), it appears that the sunspot group that just left is nearly antipodal to the current visible spot, just exiting the Sun's northwest quadrant. If they stay strong, when the current one leaves, the other should return.

Sunspot numbers for January 14-20 were 34, 26, 24, 16, 14, 0 and 16, with a mean of 18.6. The 10.7 cm flux was 89.9, 85.3, 84.2, 82.6, 81.5, 84.2 and 81.7, with a mean of 84.2. The estimated planetary A indices were 4, 3, 1, 1, 3, 1 and 14, with a mean of 3.9. The estimated mid-latitude A indices were 3, 2, 1, 1, 2, 2 and 6, with a mean of 2.4. Current prediction from USAF/NOAA has the solar flux rising from Friday, January 22-Tuesday, January 26, at 84, 85, 85, 86 and 87. Barring any unforeseen flares, the planetary A index is seen as steady and quiet at 5. Geophysical Institute Prague predicts quiet geomagnetic conditions January 22-23, quite to unsettled January 24 and quiet again January 25-28.

A Sudden Ionospheric Disturbance (SID) occurred on Wednesday after a solar flare. The Interplanetary Magnetic Field (IMF) between the Earth and the Sun was pointing south; when it points north, the Earth is less vulnerable. You can see a detailed graph of the latest orientation of the IMF here. See the graph labeled "Direction of the IMF"? It took me a while to figure out what the Y axis was for. I expected it to represent time, but it seemed to show "meters." Then I realized it was minutes, and this record covers the previous two hours. When that graph goes above 0, the Earth is protected from the effects of solar flares. Thanks to Beth Katz of the Space Weather Discussion Forum for that resource.

An SID will often cause a complete HF radio blackout, the duration varying with the intensity of the energy from the flare as it (the energy, not the flare!) reaches Earth. You can monitor SID events yourself with homemade equipment shown on a Stanford University Web site here. Note the useful links provided that lead to other pages and links, many quite useful. Check out this one and this one.

Kermit Lehman, AB1J, of Waltham, Massachusetts, commented on last week's bulletin: "I have stayed on the air, refusing to let the good be the enemy of the bad, but it hasn't been easy. Since every cloud is reputed to have a silver lining, even this valley of the shadow of the dearth of sunspots has been good for me in some ways. I was forced to figure out how to get on 40 and 80 on a postage stamp-sized piece of real estate and as a result worked, 5BDXCC -- something I would never have tried if there had been any propagation at all on 15, 12 and 10." Thanks, Kermit!

Check out K9LA's Propagation column in the current issue of WorldRadio, available free online. Click on the WorldRadio Online logo on the left side and see the Propagation column on pages 25-26. To find the obscure unnamed article he refers to under "Is there DXing on 4 MHz?" just enter a part of any phrase he quotes into your favorite Web search engine. When I did it, I got a couple of hits, but when I clicked the link for "repeat the search with omitted results included," I saw many more. Apparently that article was circulated widely, starting around 10 years ago.

In the current February issue of QST in the Up Front section, there is a piece about ham radio in the computer magazine Linux Journal. What the short item doesn't mention and isn't in the Linux Journal is the fact that the founder and publisher is a ham, Phil Hughes, WA6SWR. Phil generously gave me my first Internet access via his company back in the 1980s, years before the World Wide Web.

There is a letter in the same issue of QST from KD4SKB telling about finding some QSL cards from his Novice days back in 1971. He checked on various call sign sites on the Internet and found that three were from hams who are still licensed and had e-mail addresses. He attempted contact and got a response from one who agreed to meet him on 40 meters for a reunion QSO. He mentioned that the other fellow was 14 years old when they made contact 38 years earlier.

That reminded me of 1966, when I was 14; I brought my receiver and DX-20 CW transmitter with me on a summer visit to my grandparents in Topeka, Kansas. I strung up a wire antenna and did a little operating and ended up exchanging cards with a fellow in Illinois, about 300 miles away after a QSO on the 40 meter Novice band. When I returned to Seattle, after the QSL cards we began exchanging letters. He was two years older than me, and for a couple of years as we passed through those fast-changing stages of adolescence, we exchanged many letters, sharing the good and the bad, the terrors and the triumphs of boyhood in the late 1960s. As I recall, we shared many things that we likely might not even tell our closest friends in our home communities. We talked about radio, girls, popular music, girls, school and did I mention girls?

I had a great memory for events, people and minutia for many years, but now in my 50s, it is fading. For a number of years I have tried to recall his name or call sign so I could look him up and see if he was still a ham. But I couldn't find the logbook from that summer and I had misplaced his QSL long ago. But I waited, knowing that at some time in the future I would recall or see something that jogged my memory. Finally last spring it happened. I was looking through the June 2009 QST, and there he was -- Ed Clink, still WA9PFB, still in New Berlin, Illinois, in the Silent Keys listing. I finally remembered, but a little late. According to FCC records, he had renewed his license just three years earlier, and still had his General Class ticket.

Amateur solar observer Tad Cook, K7RA, of Seattle, Washington, provides this weekly report on solar conditions and propagation. This report also is available via W1AW every Friday, and an abbreviated version appears each Thursday in The ARRL Letter. Check here for a detailed explanation of the numbers used in this bulletin. An archive of past propagation bulletins can be found here. You can find monthly propagation charts between four USA regions and 12 overseas locations here. Readers may contact the author via e-mail.



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