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The K7RA Solar Update


There was a surprising jump in solar activity occurred this week: The average daily sunspot numbers rose nearly 55 points (that’s almost 74 percent) to 128.7, while the average daily solar flux values were up more than 28 points to 136.9. Sunspot numbers for August 30-September 5 were 118, 144, 120, 108, 156, 150 and 105, with a mean of 128.7. The 10.7 cm flux was 127.8, 130.5, 145.6, 142.3, 141.6, 137.6 and 132.7, with a mean of 136.9. The estimated planetary A indices were 4, 3, 7, 12, 32, 13 and 28, with a mean of 14.1. The estimated mid-latitude A indices were 4, 3, 8, 14, 23, 14 and 24, with a mean of 12.9.

A pair of coronal mass ejections (CMEs) on September 3 and 4 excited Earth’s geomagnetic field, causing A index values to jump. The middle latitude A index on September 2-5 was 14, 23, 14 and 24, and the planetary A index on those dates was 12, 32, 13 and 28, while high-latitude college A index (Fairbanks, Alaska) was 48, 52, 39 and 49. Solar flux predictions show the flux values peaking on September 7 at 130, then on September 8-12 the solar flux lowers to 125, 120, 115, 110 and 105. Solar flux on September 13-16 is predicted at 100, then 95 on September 17-22, then 100, 110, 115, 120 and 125 on September 23-27, and then peaking at 130 on September 28. From September 29-October 2, solar flux is predicted to be 120, then 115 on October 3-5, and 110 on October 6-7

The planetary A index is predicted to be 8 on September 7, then 7 on September 8-10, 5 on September 11-13, 10 on September 14-16, 5 on September 17-19, 10 on September 20, 8 on September 21-23, and back down to 5 on September 24-28. F.K. Janda, OK1HH, predicts our Earth’s geomagnetic field will be quiet on September 7, mostly quiet September 8, quiet-to-unsettled September 9, quiet-to-active September 10, mostly quiet September 11, quiet-to-unsettled September 12, quiet-to-active September 13, mostly quiet September 14, quiet-to-active September 15, quiet-to-unsettled September 16, quiet September 17, quiet-to-unsettled September 18, mostly quiet September 19-20, quiet-to-unsettled September 21, quiet-to-active September 22, quiet September 23-28, and active-to-disturbed September 29.

Now that August is done, our three-month moving average has an update: The average daily sunspot number for the trailing three months -- June 1-August 31 -- was 91.9. The three-month moving averages centered on July 2011-July 2012 were 63, 79.6, 98.6, 118.8, 118.6, 110, 83.3, 73.7, 71.2, 87.3, 91.5, 96.5 and 91.9. The monthly averages of daily sunspot numbers for May-August 2012 were 99.4, 90.1, 99.6 and 85.8.

NASA has a revised forecast for the peak of Solar Cycle 24, and it looks very interesting. Instead of a peak in spring 2013 -- with a smoothed international sunspot number of 60 -- the peak is now predicted for fall 2013, with the smoothed sunspot number prediction revised to 76, which is about 27 percent higher. Perhaps Solar Cycle 24 will have a double peak, the first being in fall 2011 and the second in fall 2013.

For VHF propagation, Ken Tata, K1KT, tells us to check out this website, which he says is “great for live, real time propagation, as they are derived from global APRS reports. Unfortunately, most of the rest of the world has no APRS stations. If there are E-s paths, the red plumes can be huge! For tropo predictions, check the Hepburn maps. These maps are updated daily at 1PM (EST), I believe. By using weather maps and this site, you can sometimes do your own tropo forecasts.”

Ken says, for the last hour or so of reported contacts, check here. I checked conditions in Europe on 10 meters at 1200 UTC on September 7, and saw lots of tropo and Sporadic-e propagation indicated.

Back on August 31, Jeff Hartley, N8II, reported: “The bands have gone from pretty punk to exciting in just a couple of days -- no wonder with SFI currently 135 and K1! I worked lots of over-the-pole DX yesterday, including RI1FJ (Franz Josef Land) for a new band country at 0045 UTC on 12 meters CW; this was one hour after my sunset and about 0300 in Franz Josef Land!”

Roland Anders, K3RA, of Elkridge, Maryland, reports, also from August 31: “That jump in the smoothed sunspot number really seemed to liven things up to Asia on the bands here in Maryland, especially on 10 and 12 meters. Wednesday night was a precursor of things to come, with 15 open to Mongolia, South Korea, Indonesia, and several stations in Japan as late as 0225 UTC. On Thursday morning, I worked a few Asian stations on 20 meters at 1200 or so, and at 1220, I happened to see a huge number of spots on 10 meters by Europeans. The 10 meter band map is usually pretty blank at that hour; 12 meters was open, too, but that was not nearly so unusual as the 10 meter spots. So I tuned up to 10 and immediately started working Europeans, and ran 15 of them in about 30 minutes. Then I moved to 15 CW at 1320 and worked a couple of Chinese stations that were new stations for me. After some more Europeans, I moved to 15 SSB and worked Thailand, two Indonesian stations and finished with 9N1AA at 1452.

“Friday morning, I got on 15 at 1200 and worked some Japanese stations, Kyrgyzstan, a couple of South Korean stations, China, India, a couple of Indonesian stations and Qatar. I moved to 10 meters at 1310 to work 5H3ME on CW, then to 12 for a good run of Europeans. I went back to 10 at 1500 to pick up YB4IR, then to 15 to work Indonesia, Jordan and India. At 1525, I moved to 12 meters SSB and snagged XU7AAJ! That’s several hours after his sunset, a new band country for me. Twelve meters was also good for OD5ARMY on SSB and an Israeli mobile. Friday night at midnight on 15 meters, I heard a strong Japanese stations working RX9 and could hear both sides of QSO. So I called CQ and worked some JAs!

“Here on the East Coast, I often find that when I tune 20 at 1200 and later, I find very little, if any activity, but CQing over the pole often produces Japan and other Asian stations. So if all you do is listen and look for spots, you may be missing some good opportunities. The same can be said for 17 meters, which is usually open to Europe at that hour, but Asian stations can be enticed to answer CQs. And look for those openings over the pole on 10 and 12 mid-morning East Coast time -- it’s that time of year!”

Bob Foster, N9BGC, of Waverly, Iowa wrote on September 2: “This past week saw several solid DX openings from Northeast Iowa to Eastern Europe, the Pacific and South America on 15 meters SSB. The band stayed open well past sunset. My station is very basic -- 100 W into a ground-mounted vertical. I worked Poland, Croatia, Hawaii, Brazil and Spain; not exotic DX, but quite consistent 4000-5000 miles. It was quite satisfying, considering my modest station. Normally, I have to rely on 20 and 40 meter CW for such contacts.”

Fred Laun, K3ZO, of Temple Hills, Maryland, sent comments about this year’s All Asia Phone Contest: “Given that this contest is possibly the most affected by solar effects -- since the beam headings from here to the area where the maximum number of possible QSOs is located go right through the north magnetic polar area -- I thought it would be interesting to compare my score this year to the score in last year’s contest. In 2011, with solar flux at 119, I had 96 contacts on 40 meters, 93 on 20 meters and 196 on 15 meters, with a total of 385 QSOs and 70,455 points. In 2012 with solar flux at 145, I had 19 QSOs on 40 meters, 81 on 20 meters, 298 on 15 meters and 4 on 10 meters, for a total of 402 QSOs and a score of 81,606.

“The 15 meter numbers this year would have been even more lopsided if I hadn’t had to break off great runs twice on Friday night due to equipment problems, and if I hadn’t had to shut down almost completely during the best hours to Japan on Saturday night because of thunderstorms. My 140 foot tower took a direct lightning hit at 9:45 Saturday night.

“The main difference between the two years was the existence of a great opening to Japan on 15 Saturday morning between 1200-1400 UTC. This opening did not exist during last year’s contest, when the furthest east that 15 opened in the same time frame was to Thailand. Unfortunately, the great Saturday opening this year did not repeat itself Sunday morning because of a solar proton event which had the effect of lowering the MUF over the pole in that direction; however, propagation to that area on 20 meters on Sunday morning was much better than it had been on Saturday morning, which gave me a chance to fatten up my 20 meter numbers. RU0AI registered a mind-boggling 45 dB over 9 on my S-meter during the Sunday morning run.

“The other difference of note was that I was able to make Asian QSOs on 10 meters this year, but not many -- one UA9, two HZs and an A6, but last year I didn’t have any. As always, I had no packet in the shack on purpose, so I missed some 10 meter stuff I’m sure.”

For a peek at the K3ZO antenna farm, click here and zoom in, then click on Aerial and Bird’s Eye. You can drag the image around, and also select views from four different images in four directions on the compass rose in the upper right. Quite impressive!

All times listed are UTC, unless otherwise noted.

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. You can find a guide to articles and programs concerning propagation here. Check here and 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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