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The K7RA Solar Update

07/26/2019

On Monday July 22 a new sunspot appeared, but just for one day. The magnetic signature showed it was from the current Cycle 24.

Average daily solar flux increased insignificantly from 67 to 67.3 this week.

Predicted solar flux is 68 for July 26 through August 1, then 67 on August 2 through September 8.

Predicted planetary A index is 8 on July 26-27, 5 on July 28 through August 3, then 8, 15, 15 and 8 on August 4-7, 5 on August 8-18, 8 on August 19-20, 5 on August 21, 8 on August 22-24, 5 on August 25-30, then 8, 15, 15 and 8 on August 31 through September 3, and 5 on September 4-8.

Geomagnetic activity forecast for the period July 26 through August 21, 2019 from F.K. Janda, OK1HH.

Geomagnetic field will be:
Quiet on August 2-3, 8, 13-14, 21
Quiet to unsettled on July 26-27, 29-31, August 1, 9, 15-18
Quiet to active on (July 28,) August 4, 7, (10-12,) 19-20
Unsettled to active on August 5-6
Active to disturbed – none

Solar wind will intensify on August (2-3,) 7-8, (9-14). Parenthesis means lower probability of activity enhancement.

End of the current cycle, and beginning of the new one: https://www.eurekalert.org/pub_releases/2019-07/ncfa-ot072319.php

 

Max White, M0VNG, sent this, about the Solar Wind Composition Experiment during the Apollo 11 mission: https://bit.ly/2y849cJ

Here is the latest video from Dr. Tamitha Skov, WX6SWW: https://youtu.be/Qbqku2_NgDg

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 July 18 through 24, 2019 were 0, 0, 0, 0, 11, 0, and 0, with a mean of 1.6. 10.7 cm flux was 67, 66.7, 67, 67.7, 67.3, 67.4, and 67.8, with a mean of 67.3. Estimated planetary A indices were 3, 4, 3, 8, 8, 6, and 5, with a mean of 5.3. Middle latitude A index was 4, 3, 5, 9, 11, 7, and 5, with a mean of 6.3.

 

 



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