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The K7RA Solar Update

02/25/2022

New sunspot groups appeared on February 17, 19, 20 and 21, but solar activity declined, even though sunspots were seen covering the sun every day.

Average daily sunspot number declined 21 points from 75.3 last week to 54.3 in the current reporting week, February 17-23. Average daily solar flux was down nearly 15 points from 110.1 to 95.4. On Thursday, February 24 the decline in sunspot numbers continued to 23, 31.3 points below the average in the previous seven days.

Average daily planetary A index went from 13 to 9.6, and average daily middle latitude A index was off by one point to 7.3.

Predicted solar flux is 95 on February 25, 100 on February 26-27, 105 on February 28 through March 2, 110 on March 3-4, 108 on March 5-8, 105 on March 9-11, 103 on March 12-13, 100 on March 14, 98 on March 15-16, 102 on March 17-19, 104 on March 20-22, 108 on March 23-26, 110 on March 27, 115 on March 28-29, then 112 and 110 on March 30-31, then 108 on April 1-4.

Predicted planetary A index is 5 and 10 on February 25-26, 8 on February 27 through March 3, 10 on March 4-5, 8 on March 6, 5 on March 7-10, then 15, 12 and 10 on March 11-13, 5 on March 14-18, then 8, 5, 12, 18, 15 and 10 on March 19-24, 5 on March 25-29, then 12, 15, 10 and 8 on March 30 through April 2, and 5 on April 3-6.

 

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere, February 24, 2022 from OK1HH: "Solar activity gradually declined to very low levels with a slight chance of Class C flares. The solar wind speed and particle density fluctuate irregularly. The geomagnetic field was quiet to minor storm levels. Total solar radiation, accompanied by an irregular occurrence of enhanced geomagnetic activity caused a subsequent gradual decrease to overall below-average shortwave propagation conditions. A slight improvement can be expected in connection with seasonal changes with the approaching spring equinox."

 

I regularly check propagation on ten meters using FT8, low power, and a modest full wave end fed wire antenna that is mostly indoors on the second floor of my home. Sometimes I will see my coverage on pskreporter.info/pskmap.html concentrated in an area 2000-2300 miles away in Georgia and South Carolina, which is what I saw on February 24 around 1830 UTC. Twenty-four hours earlier I saw only two reception reports, none in the USA, with one station down in central Mexico and the other way down in Southern Argentina around 53 degrees south latitude. Very odd, but this being ten meters, soon the coverage changed, and I saw coverage across the East Coast.

Using this same modest antenna on 40 meters, where it is one quarter wave long, at 0330 UTC on February 25 I see coverage all over the United States, but only one station reporting my signal in Europe, at -17 dB from IZ1CRR in JN35TD.

On his QRZ.com page he says he is a shortwave listener, and not to call him on FT8 as he is listening only.

Even if you are not an FT8 operator, you could use pskreporter.info to discover propagation paths on different bands from your local area by searching for signals received from your grid square over the previous 15 minutes. This assumes there are other stations in your grid square active at the time.

In grid square CN87 in my area, there seem to be active local stations on at all times on every band. You should probably look for stronger signals with positive signal levels if you plan to use CW or SSB.

 

Solar eruption in the news: https://abc7.com/solar-eruption-sun-image-sunspot/11589207/

 

Article about instability of sunspots: https://bit.ly/3LXYEC4

 

A blog post about recent solar events: https://bit.ly/3t9ERHa

 

New Maui solar telescope: https://bit.ly/3ImQxNb

 

February 21 update from Dr. Tamitha Skov, WX6SWW: https://youtu.be/wJaV5RnIEFE

 

For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information Service at http://arrl.org/propagation-of-rf-signals. For an explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere.

An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation. More good information and tutorials on propagation are at http://k9la.us/.

Instructions for starting or ending email distribution of ARRL bulletins are at http://arrl.org/bulletins .

 

Sunspot numbers for February 17 through 23, 2022 were 103, 53, 51, 49, 48, 38, and 38, with a mean of 54.3. 10.7 cm flux was 96.7, 93.3, 95.7, 93.3, 97.8, 95.3, and 95.5, with a mean of 95.4. Estimated planetary A indices were 5, 6, 9, 13, 12, 16, and 6, with a mean of 9.6. Middle latitude A index was 4, 5, 6, 8, 11, 13, and 4, with a mean of 7.3.

 

 



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