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The K7RA Solar Update

11/22/2019

We have not seen any sunspots since November 2, and at that time they were only visible for two days, and prior to that no sunspots since October 2.

According to Spaceweather.com, that recent sunspot, though very short lived, was a new Cycle 25 spot: https://bit.ly/2KJ7cyy

The average daily solar flux this week dipped slightly from 70.3 to 69.9. Geomagnetic conditions were quiet, with average daily planetary A index receding marginally from 4 to 3.6, and average mid-latitude A index going from 3 to 2.3.

Predicted solar flux is 70 on November 22-23, 68 on November 24 then 67 on November 25-28, 69 on November 29 through December 8, 70 on December 9-22, and then 69 on December 23 through January 4 and 70 on January 5.

Predicted planetary A index is 16, 10 and 8 on November 22-24, 5 on November 25 through December 12, 6 on December 13, 5 on December 14-15, then 8, 15, 20, 18 and 10 on December 16-20, 8 on December 21-23, and 5 on December 24 to January 4.

Geomagnetic activity forecast for the period November 22 until December 17, 2019 from OK1HH.

Geomagnetic field will be:
Quiet on: November 29-30, December 1, 10-16
Quiet to unsettled on: November 27-28, December 2, 7-9, 17
Quiet to active on: November (25-26,) December 3-6
Unsettled to active on: November 23 (-24)
Active to disturbed: November (22)

Solar wind will intensify on: November 22-24, (25-26) December (3-9, 13-14,) 16-17

Parenthesis means lower probability of activity enhancement.

Fred, ND4DX shared the following: "Your comment about how amazing long distant contacts are still possible with present conditions brought back memories of the VP6DX expedition to Ducie Island 11 years ago during another solar minimum. I was able to work them SSB on all phone bands, 80-10 meters, with 100 W mobile using with Hustler/Hamstick antennas. I’ll bet if I looked through the log at other solar minimums, I’d see similar results. So, I think all this worry folks have over the solar minimum is unfounded. Yes, sunspots make it easier, but now it is even more challenging and interesting with pretty much the same results. I’ve found that to be true using just 100 W and my 43-foot vertical antenna.”


David P. Moore sent two articles on solar physics: https://bit.ly/2KL6sJk and https://bit.ly/2XzVBqS

Tamitha Skov, WX6SWW, gives us a timely forecast video : https://youtu.be/WrIsipdOfF0

Here is an interesting resource from Japan, showing daily sunspot data beginning in 1929: https://solarwww.mtk.nao.ac.jp/en/db_sunspot.html

 

Don’t forget that this weekend is the CW portion of the CQ Worldwide DX Contest: https://www.cqww.com/

If you would like to make a comment or have a tip for our readers, email the author at k7ra@arrl.net.

For more information concerning radio propagation, see 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/.

Monthly propagation charts between four USA regions and twelve overseas locations are at http://arrl.org/propagation.

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

Sunspot numbers for November 14 through 20, 2019 were 0, 0, 0, 0, 0, 0, and 0, with a mean of 0. 10.7 cm flux was 69.9, 70, 69.7, 70.1, 70.4, 69.2, and 70.2, with a mean of 69.9. Estimated planetary A indices were 4, 4, 6, 5, 2, 2, and 2, with a mean of 3.6. Middle latitude A index was 3, 2, 5, 3, 1, 1, and 1, with a mean of 2.3.

 



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