February 24, 2024

This Week in Amateur Radio

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Via the ARRL: The K7RA Solar Update 08/26/2022

On August 18 a new sunspot group emerged, another on August 21, then two more on August 23, and three more on August 25, when the sunspot number jumped to 94 from 46 the previous day.  Total sunspot area more than doubled from Wednesday to Thursday.

Solar activity overall was down slightly for the reporting week, August 18-24, with average daily sunspot number declining from 60.8 during the previous seven days to 58.7, and average solar flux from 123.7 to 104.5.

Planetary A index changed from an average of 11.7 to 12.6, and middle latitude A index measured at a single magnetometer in Virginia was 11, after an average of 10 last week.

As an indicator of rising solar activity, a year ago this bulletin reported average daily sunspot number at 17.7, 41 points below this week’s report.

The Thursday night forecast from the 557th weather wing at Offut Air Force Base shows a probable peak of solar flux for the near term at 130 on September 11 and again on October 8.

Predicted solar flux is 120 on August 26-27 (up from 105 in the previous day’s forecast), 115 on August 28, 110 on August 29-31, 115 on September 1-2, 116 on September 3-4, 112 on September 5, 108 on September 6-7, then 115, 120, 124 and 130 on September 8-11, then 128, 120, 118, 105 and 102 on September 12-16, 98 on September 17-18, 96 on September 19-21, 94 on September 22-24, then 92, 98 and 100 on September 25-27, then 108, 114, 116 and 116 on September 28 through October 1.

Predicted planetary A index has some surprises in store, at 5 on August 26, 8 on August 27-28, 10 on August 29, 5 on August 30-31, 8 on September 1-2, then jumping way up to 30, 38 and 20 on September 3-5, then 15, 18, 10, 12 and 8 on September 6-10, 5 on September 11-12, then 12, 15 and 10 on September 13-15, 8 on September 16-17, then 25, 15 and 8 on September 18-20, 5 on September 21-22, 12 on September 23, then  8 on September 24-26, 5 on September 27-29, then back up to 30, 38, 20, 15 and 18 on September 30 through October 4, an apparent echo of the prediction for September 3-7.

The above predictions were from USAF forecasters Easterlin and Sadovsky.

F.K. Janda, OK1HH wrote:

“As in the previous solar rotation, the Sun’s activity continued to decline. Geomagnetic activity, however, has increased. More pronounced eruptive activity was mainly in the southwest quadrant of the solar disk.

“The active sunspot, AR3078, produced several M-class solar flares and more than a dozen C-class flares. Most of the eruptions hurled particles into space. The first CME hit Earth’s magnetic field on August 20. The next active sunspot group, AR3085, behaved similarly after reaching the same active heliographic longitude as the previous sunspot, AR3078.

“Sunspot AR3085 grew more than ten times larger and turned into a double sunspot group with cores almost as wide as the Earth. Finally, a new sunspot, AR3088, appeared, again in the southern hemisphere of the Sun.

“Attention is now drawn to a large coronal hole in the southeastern solar disk that could affect the solar wind after it appears near the central meridian.

“With the current type of development, predictions of further events are more difficult than usual. Either way, we now expect a quasi-periodic increase in solar activity.”

Here is a news article about a large sunspot:


British tabloid sunspot news:


Here is an article about a planet-sized sunspot:


A Nature World News story about a big sunspot:


A report about eleven discoveries and the coming solar max, from American Geophysical Union:


From Space.com, the threat of unexpected flares:


Here is a paper on solar rotations:


I did not include an article titled “Destructive solar storms are possible as Sun approaches height of its terrifying solar cycle.” The article claimed that Solar Cycle 25 peak will be a year from now, rather than the consensus prediction of 2025.

Send your tips, reports, observations, questions, and comments to
k7ra@arrl.net .

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Sunspot numbers for August 18 through 24, 2022 were 83, 74, 56, 56, 44, 52, and 46, with a mean of 58.7. 10.7 cm flux was 116.5, 105.4, 101.5, 97, 102.6, 100.9, and 107.8, with a mean of 104.5. Estimated planetary A indices were 26, 20, 14, 14, 7, 4, and 3, with a mean of 12.6. Middle latitude A index was 19, 15, 16, 13, 7, 3, and 4, with a mean of 11.

Read more – via American Radio Relay League | Ham Radio Association and Resources http://www.arrl.org/news/view/the-k7ra-solar-update-743