venerdì 2 agosto 2019

The K7RA Solar Update

No sunspots were observed over the past week, and solar flux remains flat, with average daily values declining from 67.3 to 67.

Average daily planetary A index went from 5.3 to 5, and middle latitude A index from 6.3 to 5.9.

Predicted solar flux for the next 45 days remains at 67, August 2 through September 15, every day.

Predicted planetary A index is 5 on August 2-3, then 8, 18, 15, 12 and 8 on August 4-8, 5 on August 9-16, 8 on August 17-18, 5 on August 19-26, then 8, 16, 8, 5, 8, 22 and 16 on August 27 through September 2, 5 on September 3-12, 8 on September 13-14, and 5 on August 15.

Geomagnetic activity forecast for the period August 2-28, 2019 from F.K. Janda, OK1HH.

Geomagnetic field will be: 
Quiet on August 2-3, 8, 12-15, 21-22 
Quiet to unsettled on August 9, 16-17, 23, 25 
Quiet to active on August 4-5, 7, (10-11,) 19-20, 24, 28 
Unsettled to active on August 6, (18, 26-27) 
Active to disturbed-None!

Solar wind will intensify on August (2-3,) 6-8, (9-14,) 27-28

Parenthesis means lower probability of activity enhancement.

Spaceweather.com reminds us, "BE ALERT FOR PERSEID FIREBALLS: Earth is entering a stream of debris from giant Comet Swift-Tuttle, source of the annual Perseid meteor shower. Forecasters say the shower won't peak until Aug. 12-13, but already NASA cameras are catching Perseid fireballs streaking over the USA. The Perseids produce more fireballs than any other annual shower--largely due to the size of the parent comet--so your chances of seeing one are good."

Larry Koziel, K8MU, sent this, about simulating the Sun in a lab: https://bit.ly/2LQLP0N

Larry and several others including Max White, M0VE, reported recently about solar tsunamis: https://bit.ly/2OvhlDr

George, N2CG, in Saddle Brook, New Jersey wrote on July 29: “So far this year's Summer Es season daily FT8 openings between North America and Europe on 6 meters have mostly bypassed the FN20 and adjacent grids. They seem to favor the southeast (especially grids EL and EM) as seen daily on the DXMAPS Website.

“Whatever European openings I did manage to work so far were short lived, lasting just a few minutes to 20 minutes at best. However, that changed on Sunday July 28, 2019 beginning around 2100 UTC in southeast and around 2200 UTC at my location in New Jersey, when Finnish, Swedish, and Norwegian stations were copied on FT8 for more than an hour. I managed to decode the following stations: OH2MA, OH2FQV, OH2FNR, OH3XF, LA2XPA and SM3CCM, and I worked OG2M, OH3SR and OH3XA. This was my first time working Finland on 6 meters, and shortly after my contact OH3SR he verified our QSO on LoTW!

“August will bring the prime 6-meter Es season to a close. However, maybe the 6-meter gods have another surprise opening before the end of the season."

The latest video from WX6SWW: https://youtu.be/UpyFOZLacvw

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 25 through 31, 2019 were 0, 0, 0, 0, 0, 0, and 0, with a mean of 0. 10.7 cm flux was 68.2, 67.6, 66.7, 67.1, 66.1, 66.2, and 66.9, with a mean of 67. Estimated planetary A indices were 3, 3, 4, 4, 5, 8, and 8 with a mean of 5. Middle latitude A index was 3, 4, 4, 7, 5, 8, and 10, with a mean of 5.9.