The K7RA Solar Update


Good conditions should prevail for the CQ World Wide SSB DX Contest this weekend. A chance for solar flares has greatly diminished in the past few days, and the latest forecast has the planetary A index at a steady and quiet 5 for this weekend and beyond, through the first week in November.

The average daily sunspot numbers for October 18-24 were down 1.7 points from the previous seven days, to 95.3, while the average daily solar flux rose 14.7 points to 143.9. Sunspot numbers for October 18-24 were 112, 120, 112, 75, 86, 84 and 78, with a mean of 95.3. The 10.7 cm flux was 137.6, 141.4, 151.4, 144.2, 155.6, 141.6 and 135.6, with a mean of 143.9. The estimated planetary A indices were 5, 4, 3, 3, 3, 7 and 4, with a mean of 4.1. The estimated mid-latitude A indices were 4, 3, 3, 2, 2, 9, and 6, with a mean of 3.7.

Geomagnetic activity was quieter, with all daily planetary A index measures in the single digits. As of October 26, NOAA and the US Air Force are predicting the solar flux to be at 125 on October 26, 120 on October 27, 115 on October 28-29, 110 on October 30-31, 105 on November 1-2, 100 on November 3, then 105 and 110 on October 4-5, 115 on October 6-7, 120 on November 8-11, 125 on November 12-13, then peaking at 145 on November 18 and dropping back to 100 on November 29-30. It then rises to 120 on December 5-8. This is a substantial downward revision from the previous day’s forecast (as presented in the October 25th edition of The ARRL Letter), which showed solar flux at 135 on October 25-26, 130 on October 27-29, 125 on October 30-November 1, and 100 on November 2-3.

You can check the actual solar flux directly from the Penticton, British Columbia observatory today sometime after 2000 UTC. Three readings per day are shown: at 1700, 2000 and 2300 UTC, and the local noon (2000 UTC) value becomes the official one for the day. The way to read it is to scroll all the way to the bottom of the page, then in the first column is the date (expressed as 20121026) and the second is the time, 200000 for 2000 UTC. Then for the observed solar flux, skip over to the fifth column to the right. You can see that yesterday the three values were 132.2, 130.0 and 129.2, and so 130 became the official flux value for October 25, as reported by NOAA. Note the Penticton observatory resolves the number to one more decimal place than the report from NOAA, which rounds it to the nearest whole number.

The predicted planetary A index is 5 on October 26-November 7, then 10, 20 and 15 on November 8-10, 5 on November 11-17, 10 on November 18-19, and back down to 5 on November 20-December 4.

Sunspot group 1598 emitted a powerful X-1 class solar flare on October 23, and it is now rotating into the center of the solar disc today. But it shrunk in the past couple of days, and now the chance of flares has declined to just 5 percent, according to NOAA forecasters. The shrinking of the formerly giant sunspot led to declining solar flux predictions and should ease any worries about this weekend.

Check out this video showing sunspot group 1598 and the recent flare. Note the position of the sunspot projected the flare away from Earth. Also, please ignore the videos previewed on the right side of the screen, which on my display show nonsense about the end of the world, grand planetary alignments, phantom rogue planets, the scary “Planet X” and probably channeling your past lives using crystals. Old time hams know that crystals are only good for channelizing radios.

Jeff Hartley, N8II, of West Virginia writes on October 22: “Regarding peak signal directions during very disturbed conditions, they tend to peak farther south in general and seem to divert the most on 20 meters, but I don’t have any Yagis below that band. Stations in Russia and Central Asians in Zone 18 -- which normally peak 0-10 degrees -- were peaking around 330-350 as an event was just starting. The next morning, stations in VK6 -- which usually peak around 310 -- were best around 280-290 degrees. Japanese stations on 20 sometimes peak due north, where the true heading is 330 during low K index periods.

“Don't forget long path: Around 2000 on October 21, T30PY was long path on 15 SSB about S3, but not hearing well. Later, at 2300, they were about the same strength short path and hearing people better. I also worked A71EM long path on 17 CW around 1400. The Middle East is often better long path in our mornings on 20 than short path, but they come through well short path from 1900, sometimes all the way through their sunrise.

“Conditions were quite good over the weekend (October 20-21). I had a solid run of Russian stations on 10 meter CW starting around 1200 Saturday, including many UA9s in Zone 17; one UN0 also made it thru with an S3 signal. OH6NT called in with a 25 dB over S9 signal. I was busy with the family Saturday evening, but Sunday evening and afternoon were definitely above recent normal conditions, with very late openings to Europe and Africa on all bands, including 3B9SP on 10 CW at 2030. In the morning, the Asian and Russian stations were not as good on 10 Sunday, but I did log VU2MGS on 10 CW. Sunday evening was quite good, and I worked BA7IO on 10 CW about 90 minutes past sunset and JA8CMC was S9 along with a CQ answer from UA0IT, who was S5-7 with only a vertical antenna.”

Pat Ryan, KC6VVT, of Tonica, Illinois (EN51), reported on October 20: “Ten meters opened yesterday between the US and Europe, and many stations appeared on 10 as word spread via Facebook. I heard IZ7NLJ running 400 W into his home brew Yagi antenna, and CT1DVV -- both working the US pileups! I used my 100 W radio and 10 meter resonant vertical whip antenna on my mobile parked in my driveway to work Augi from club station 9A1CCB in Croatia (JN85) and Karel, OK1CF, in the Czech Republic (JO60) from 1558-1608 UTC. Later, around 1742, from the inside station (using 100 W into a 5-band ribbon dipole, 20-10M), I worked Antonio, CU3AG, in Azores Island (HM68).”

Pete Markavage, WA2CWA, of Sayreville, New Jersey, reports: “On October 18, I had a great morning on 10 meters AM. The band opened around 9:30 AM into Europe, and I worked OR0A, GW8TBG, DB5ZP, UU5AI, G8ETD, G4ZXN, G4CZU, EA1GGX, UZ2HZ, G4FHI, RK6DP, GW0AGZ, GU4LJC, G7OSR, MM0OPX, GW3TMP, G3XGW, G3YBY, SM0ZCQ, G3VWH, SM2A and ON3KA. AM is alive and well on the upper end of 10 meters. I was running about 100 W into an old tri-bander up about 40 feet.”

Last week’s Solar Update mentioned Joe Dawson, K4WLS, of Atlanta, Georgia and his Slinky antenna. He wrote again on October 19 about a Slinky-to-Slinky QSO: “I spoke to a ham in Italy on 10 meters this morning who is running the same mini slinky antenna. He tells me that the low take off characteristics of the antenna make it his DX choice on 10 and 12 meters. I got a slinky junior antenna to use on a camping trip. I put it up to test it as an inverted V on my back deck. It has worked magic on 17, 15, 12 and 10 meters. I would not have believed it, since I thought it would tune to 20 and 40, due to the electrical length. Well, it does not tune to 20 and 40, but DX contacts galore on the upper four HF bands. I love it!”

Lee Gordy, KJ4KUT, of Cartersville, Georgia wrote: “When 10 is in, then you can load just about anything and make some DX contacts with low wattage. My uncle W4TIY (SK), a former FCC Monitoring Engineer, was stationed in Texas at the end of World War II. He had rented a room at a boarding house. ‘Ten was In,’ so he loaded the metal bedsprings – literally – and made some really good contacts.”

And finally, Don Kalinowski, NJ2E, of Cary, North Carolina, sent along this interesting and entertaining video about the NASA Radiation Belt Storm Probes. Watch it at and note that you can expand this all the way to double normal resolution by clicking on the asterisk-like “Change Quality Control” at the bottom, then click on “Full Screen” all the way to the right.

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.