[South Florida DX Association] ARLP039 Propagation de K7RA

[Bill Marx]

 To all radio amateurs 
> 
> SB PROP ARL ARLP039
> ARLP039 Propagation de K7RA
> 
> Average daily sunspot numbers this week were down nearly 31 points
> to 13.4, and average daily solar flux declined over 8 points to 77.
> Sunday through Thursday of this week, the sunspot number was 11 on
> all five days.  Sunspot activity should remain low.
> 
> This week a coronal wind stream caused a geomagnetic disturbance
> centered on September 18.  A week ago, on Friday, September 15,
> geomagnetic conditions were very stable.  The mid-latitude K index
> throughout the day was zero on all eight readings, and so the
> mid-latitude A index was also zero.  Even the high latitude college
> A index near Fairbanks, Alaska was zero that day.
> 
> Due to a recurring coronal hole, we may see a rise in geomagnetic
> activity this weekend, with the planetary A index predicted at a low
> of 5 on Friday, then rising to 20 on Saturday, September 23.
> 
> Today a group of satellites should be launched that will give
> 3-dimensional views of solar flares.  The plan is to view flares
> from two satellites, spaced far enough apart to give stereo vision.
> Jerry Reimer sent a link to an article about this in Britain's
> Sunday Times. Read it at http://tinyurl.com/rejj8.
> 
> Yvone Dubois, KE7HTQ of Phoenix asks, ''Where can I find propagation
> charts old style, like they used to be published in QST for
> decades?''
> 
> The charts have moved from the magazine to the web.  Find them at
> http://www.arrl.org/qst/propcharts/
> 
> If you would like to make a comment or have a tip for our readers,
> email the author at, k7ra at arrl.net.
> 
> For more information concerning radio propagation, see the ARRL
> Technical Information Service at
> http://www.arrl.org/tis/info/propagation.html. For a detailed
> explanation of the numbers used in this bulletin, see
> http://www.arrl.org/tis/info/k9la-prop.html. An archive of past
> propagation bulletins is at http://www.arrl.org/w1aw/prop/ .
> 
> Sunspot numbers for September 14 through 20 were 25, 12, 13, 11, 11,
> 11 and 11 with a mean of 13.4. 10.7 cm flux was 82.8, 80.1, 79.2,
> 78, 74.4, 73.4, and 70.9, with a mean of 77. Estimated planetary A
> indices were 6, 3, 3, 16, 24, 12 and 5 with a mean of 9.9. Estimated
> mid-latitude A indices were 4, 0, 1, 9, 16, 8 and 3, with a mean of
> 5.9.
> NNNN
> /EX
>