[South Florida DX Association] ARLP019 Propagation de K7RA

[Bill Marx]

SB PROP ARL ARLP019
> ARLP019 Propagation de K7RA
> 
> This week saw higher geomagnetic activity and lower sunspot numbers
> than the previous period (our reporting week is Thursday through
> Wednesday). Average daily sunspot numbers declined over five points
> to 54.3. For today, May 12, look for active geomagnetic conditions,
> with a planetary A index predicted at 25, then declining to 12 and
> 10 on Saturday and Sunday. Sunspot numbers and solar flux should be
> a bit lower than the past week.
> 
> Geophysical Institute Prague predicts active geomagnetic conditions
> for today, May 12, unsettled May 13, quiet to unsettled May 14, nice
> and quiet on May 15-16, back to quiet to unsettled for May 17, and
> unsettled conditions on May 18.
> 
> A rash of email arrived this week alerting us to a new long-range
> sunspot cycle prediction. Only this time it isn't for upcoming cycle
> 24, but the peak of cycle 25, reaching solarmax around 2022.
> 
> Think that's a long way off? It depends on your perspective, which I
> suspect is determined by the proportion a given time period
> represents when compared to the time you've been alive. For
> instance, when starting out in early 1965 as WN7CSK, and still 12
> years old, looking ahead 16 years I would be 28, and the year 1981,
> hard to fathom at the time. The old-timers I knew then, such as
> Howard S. Pyle, W7OE, first on the air around the same age in 1907,
> would have laughed out loud at such an assessment.
> 
> This spring it was 16 years since I began writing this bulletin.
> And 16 years from now, in mid 2022, I will turn 70, a terrifying
> notion, because the last 16 years went by so fast. I suspect the
> next 16 years to flash by quickly. Even if beginning our ham life at
> a young age, we don't get to see many solar cycles. Let's hope the
> soon-to-begin cycle 24 is huge, reminiscent of the awesome cycle 19
> of the 1950s.
> 
> We saw a prediction in March that the upcoming cycle 24 could be a
> big one, from a recent prediction by Mausumi Dikpati. (See the 2006
> Propagation Forecast Bulletin ARLP010 at,
> http://www.arrl.org/w1aw/prop/2006-arlp010.html, and the NASA
> article at,
> http://science.nasa.gov/headlines/y2006/10mar_stormwarning.htm.
> 
> Using the same method of indirectly observing a massive circulating
> current of solar plasma, a report from NASA solar physicist David
> Hathaway shows a stunted-looking cycle 25. Read about it in an
> article from Dr. Tony Phillips at,
> http://science.nasa.gov/headlines/y2006/10may_longrange.htm?list15934.
> 
> Roger Barnhill, AB8RX of Lansing, Michigan asks, "Where can I find
> up-to-date info on which way the Earth's magnetic field is pointing
> at any particular time?"
> 
> You can find this at http://www.spaceweather.com/. Look down the
> left side under Interplanetary Magnetic Field. When it is pointing
> south, Earth is vulnerable to solar wind, and more likely to
> experience greater geomagnetic activity.
> 
> HS0ZFQ sent in a link to a page titled, "The short history of the
> Smoothed Sunspot Number" at,
> http://www.astrosurf.com/lombry/qsl-ssn-history-voacap.htm. This
> discusses the various sources for smoothed sunspot numbers needed
> for propagation prediction programs using the VOACAP (Voice of
> America Coverage Analysis Program) engine. One example called HamCAP
> is from VE3NEA. It is free, and you can get it at,
> http://www.dxatlas.com/hamcap/.
> 
> Mike Schaffer, KA3JAW is in Florida, where he enjoys observing
> sporadic-E propagation on broadcast television. On May 11 at 1750z
> and again at 2215-2230z he observed Canal 2 on television channel 2,
> about 1100 miles from him in Nicaragua.
> 
> 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 and an explanation
> of the numbers used in this bulletin, see the ARRL Technical
> Information Service propagation page at,
> http://www.arrl.org/tis/info/propagation.html. An archive of past
> propagation bulletins is at, http://www.arrl.org/w1aw/prop/.
> 
> Sunspot numbers for May 4 through 10 were 50, 61, 69, 64, 53, 56 and
> 27 with a mean of 54.3. 10.7 cm flux was 91.8, 86.7, 87, 86.2, 84.7,
> 82.6, and 78.2, with a mean of 85.3. Estimated planetary A indices
> were 14, 13, 24, 19, 8, 4 and 4 with a mean of 12.3. Estimated
> mid-latitude A indices were 10, 8, 14, 17, 5, 2 and 4, with a mean
> of 8.6.
> NNNN
> /EX
> 
>