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The K7RA Solar Update


Solar activity jumped way up this week, with the average daily sunspot numbers increasing by nearly 92 points to 118.1, while the average daily solar flux rose to 138.5 from 92.8 the week before. One new sunspot group appeared on June 29, another on July 1 and two more on July 4. Sunspot numbers for June 28-July 4 were 73, 97, 90, 137, 165, 136 and 129, with a mean of 118.1. The 10.7 cm flux was 119.7, 117.4, 124, 133.4, 165.9, 145.8 and 163.2, with a mean of 138.5. The estimated planetary A indices were 6, 5, 22, 19, 19, 10 and 9, with a mean of 12.9. The estimated mid-latitude A indices were 7, 6, 21, 20, 18, 11, and 11, with a mean of 13.4.

Geomagnetic activity this week focused on the usual suspects, solar flares and solar wind spewing from coronal holes. One unusual aspect was that the mid-latitude A index, measured in Virginia, was actually higher on July 3-4 than the planetary A index, which is usually higher. The planetary A index is made up of an weighted aggregate of estimated K index data from multiple geomagnetic observatories.

The outlook for the near term has changed since the forecast that was presented on Thursday in The ARRL Letter. The solar flux is higher, and the higher geomagnetic activity is due to an M-class solar flare on July 4. The forecast shows increasing activity over the next couple of days, with solar flux at 165 on July 6-7, 160 and 155 on July 8-9, 145 on July 10, 140 on July 11-12, then 130, 125, 115 and 110 on July 13-16, and then 105 and 100 on July 17-18. Solar flux is expected to dip below 100 on July 19-22, but look for it to rise to 140 on July 30-August 1, dip again and then peak at 145 on August 7. The planetary A index is expected at 8, 12, 22, 18, 8 and 7 on July 6-11, and 5 on July 12-26, followed by another active period with the planetary A index at 20 on July 27-28, 15 on July 29-30 and 8 on July 31-August 1. A index should go quiet down to 5 over the next couple of weeks, except for a reading of 8 on August 4.

Petr Kolman, OK1MGW, of the Czech Propagation Interest Group predicts the geomagnetic field will be quiet-to-unsettled July 6-7, quiet-to-active on July 8, unsettled-to-active July 9, mostly quiet on July 10-12, unsettled-to-active July 13-15, mostly quiet on July 16-18, and quiet-to-unsettled on July 19-21.

The Australian Space Forecast Centre issued a Geomagnetic Disturbance Warning at 2328 on July 5. It predicted quiet-to-unsettled conditions July 6, quiet-to-unsettled conditions with active to minor storm periods late in the UTC day on July 7, and unsettled-to-active conditions with isolated minor storm periods on July 8. This alert comes from a mail list offered by the Australian Government Bureau of Meteorology.

As June is now over, we can look at some monthly numbers and three month moving averages. For the three month periods centered on January-May 2012, the average daily sunspot numbers were 83.3, 73.7, 71.2, 87.3 and 91.5. Keep in mind that the three month average centered on May is an arithmetic average of all daily sunspot numbers from April 1-June 30. If we look at just the monthly sunspot number averages for September 2011-June 2012, they are 106.4, 123.6, 133.1, 106.4, 91.4, 50.1, 78, 84.5, 99.4 and 90.1.

That period last fall when sunspot numbers were so high was unusual, or at least we hadn’t seen activity such as that in a long time. It was eight years earlier -- in November 2003 -- when the monthly average of daily sunspot numbers was over 100 previous to September 2011. In November 2003, the average daily sunspot number was 103, and in October 2003 it was 118.9. It hadn’t passed the November 2011 average of 133.1 since nine years ago when it was 132.8 in July 2003; on July 20, 2003 the daily sunspot number was 224.

Check out this article on a recent solar flare. NASA even had a comment.

Following last week’s reports, another ARRL Field Day report came in on July 3 from Billy Bagwell, KE5WLH, of the Greyhound Amateur Radio Club at Eastern New Mexico University in Portales, New Mexico. Billy wrote: “K5R -- the special event station celebrating 100 years of New Mexico statehood -- had three radios on 80, 40, 20 and 15 meters. We made plenty of contacts on all bands. Eighty got better here after 9 PM local time and was great most of the night, with times of noise and fading. We think this was due to sun event/magnetic activity. Twenty and 40 were hot as we expected, and 15 meters started slow at noon and moved with the Sun from east to west until sunset, when it seemed to fade away. On Sunday at sunrise, 15 meters came back hard and moved with the Sun as expected. We had our stations set up in the Roosevelt County Sheriff’s Office EOC, and all involved had a great time!”

On June 30, Bob Leo, W7LR, of Bozeman, Montana, wrote about a “giant 6 meter opening yesterday morning, the best that I have ever heard in 75 years of hamming. The band was full of distant DX. I even worked Israel, Poland, Estonia and Svalbard with 100 W -- all new ones for me -- between 1300 to 1500 when the band folded. Today it is as dead as a fence post.” Bob was born in 1921 and was on the famous Hallicrafters’ expedition to Africa in 1948. Check out his bio.

Joe, CT1HZE, of Portugal (IM57nh) reports: “June 30 was definitely an historic day for 6 meter multi-hop E-skip. Already, from 0430, observers in Finland received FM broadcast stations from Russia on 70 MHz, indicating a MUF >110 MHz at high latitudes of up to 70 degrees North. These E-skip clouds shifted westerly with the Sun and at about 1300, a spectacular 6 meter opening started when the automatic keyer from NN7J (CN85, Beavercreek, Oregon) was heard simultaneously by G0JHC, CT1HZE and stations in Germany. In the following six hours, stations in the Pacific Northwest from W6, W7, VE7, VE6 and VE5 were able to work hundreds of QSOs with many countries in Western, Central, and Eastern Europe. Due to the early local time on the West Coast, probably many stations missed the first hours of the opening and later on some had to go to work, of course. I would consider this as a multi-hop E-skip propagation event with high MUF (>70 MHz) on huge parts of the paths and probably more hops than necessary for the distance.”

Thanks, Joe and Bob. What an opening!

Kevin Lahaie, K7ZS, of Hillsboro, Oregon, wrote on June 29: “Out of the blue, Europe opens this morning on 6 meters in a big way! I just worked Germany, France, Scotland, Sweden, Poland, Belgium, Sicily and Denmark on 6 meter CW. Yahoo!”

Apparently the opening may have favored the Northwest and not the Southwest. I hope he wasn’t so discouraged that he missed the opening, but early on June 29, Lance Wilson, NR7N, of Scottsdale, Arizona wrote: “I have been on 6 meters for 50 years and I must say that the E-skip season in the Southwest has been disappointing. We have had a few good openings this year to the East Coast, but nothing like previous years. International DX is non-existent. I keep watching reports on extensive East Coast-to-Europe openings (as well as extensive US openings for them as well) while we on the other side of the country go empty handed. While working Europe from the west normally requires F2, it appears that something else may be at play here: Day after day of seeing the left-hand lower quarter of the US virtually blank makes me wonder what could be going on. Openings, when they occur, are mainly to the northwest, with some also to the middle of the country. Even our normal pipeline to Texas appears to be down.”

Regarding conversion of Command sets to SSB -- a topic mentioned in recent bulletins -- Ray Soifer, W2RS, of Green Valley, Arizona wrote: “The W2EWL conversion didn't exactly convert a Command set to SSB, it made it into a VFO to use with an SSB exciter. In the 1950s, I had a Central Electronics 20A exciter and a converted BC-458 VFO. The 20A generated SSB (upper sideband) at 9 MHz. Mixing that with the 5 MHz output of the BC-458 produced USB on 20 meters or LSB on 80.”

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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