QST de W1AW  
Propagation Forecast Bulletin 43  ARLP043
>From Tad Cook, K7RA
Seattle, WA  October 21, 2016
To all radio amateurs 

SB PROP ARL ARLP043
ARLP043 Propagation de K7RA

Over the past reporting week (October 13-19) compared to the
previous seven days average daily sunspot number declined from 55 to
31, while average daily solar flux dropped from 101.9 to 83.4.

Planetary A index increased from 6.6 to 19.1, and average
mid-latitude A index jumped from 5 to 14.

This is the opposite of what happened two weeks ago compared to last
week, when A indices decreased but solar flux and sunspot numbers
rose.

The latest prediction for solar flux (from the October 20
prediction) shows these values: 75 on October 21-23, 72 on October
24, 75 on October 25-26, 80 on October 27, 75 on October 28-29, 80
on October 30, 85 on October 31 through November 5, 90 on November
6-8, 85 on October 9-11, 80 on November 12-14, 75 on November 15-19,
70 on November 20-22, 75 on November 23-25, 80 on November 26 and 85
on November 27-30.

Predicted planetary A index is 5 on October 21, then 22, 24 and 40
on October 22-24, then 44, 40 and 22 on October 24-27, 15 on October
28-30, 25 on October 31, 12 on November 1, 5 on November 2-5, 8 on
November 6, 5 on November 7-10, then 10, 24, 26, 12 and 8 on
November 11-15, 5 on November 16-17, then 12 and 22 on November
18-19, 35 on November 20-22, 20 on November 23, 15 on November
24-26, 25 on November 27, 12 on November 28 and 5 from November 29
to December 2.

Petr Kolman, OK1MGW of the Czech Propagation Interest Group sent the
following geomagnetic activity forecast for the period October
21-November 16, 2016.

'Geomagnetic field will be:

'Quiet on November 7-8
Mostly quiet on November 3-4, 9-11, 15-16
Quiet to unsettled on October 21, November 1-2, 5-6, 14
Quiet to active on October 22-23, 29-31, November 12-13
Active to disturbed on October 24-28

'Amplifications of the solar wind from coronal holes are expected on
October 22-31, November 5-6, 11-13.'

Here is a web article about a nearby star which seems to exhibit
sunspot activity:

bit.ly/2enuNmR

Another solar article, but this one regarding our own Sun:

bit.ly/2eYtKNJ

Reader Roger Larson, KF6IVA of Harrison, Maine says he uses an
inexpensive alternative to solar telescopes called the Sunocular. A
week ago he sent this message: 'You can buy a special pair of
binoculars (Sunoculars, 8x32 binoculars with a special coating) that
allow you to observe the Sun. I can see a big sunspot headed off to
the western limb, other that the Sun is featureless.'

A week later he wrote: 'The Sun was featureless yesterday. With
these 'sunoculars' you can make out large sunspots and therefore get
an idea of how active the Sun is. I have seen specialized solar
telescopes which would show more due to their higher magnification
but they cost a thousand dollars plus.'

Here is the last correspondence from Roger, received just as I was
completing this bulletin:

'They work pretty well realizing that they are only good for
observing the Sun. I imagine that you've looked at the Moon with
binoculars, the Sun is roughly the same angular dimensions (30 arc
minutes).  The Moon has a lot of features visible in 8 power
binoculars, the Sun is featureless unless there's a large
sunspot(s). Along the edge of the Moon you'll see some 'rainbow'
effects due to imperfections in the lens unless you look with
expensive binoculars. Well there are a few of these rainbow effects
visible in the Sunoculars no worse than any other binoculars I've
used. The objective lens are coated with a material that allows
ten-millionth (1x10-5) of the light to pass through. The Sun appears
about as bright as a full Moon in them.'

If you would like to make a comment or have a tip for our readers,
email the author at [email protected].

For more information concerning radio propagation, see the ARRL
Technical Information Service web page at,
arrl.org/propagation-of-rf-signals. For an explanation of the
numbers used in this bulletin, see
arrl.org/the-sun-the-earth-the-ionosphere. An archive of past
propagation bulletins is at
arrl.org/w1aw-bulletins-archive-propagation. More good
information and tutorials on propagation are at k9la.us/.

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

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

Sunspot numbers for October 13 through 19 were 41, 38, 35, 25, 23,
24, and 31, with a mean of 31. 10.7 cm flux was 95.3, 92.8, 84.9,
80.9, 76.2, 77.4, and 76.5, with a mean of 83.4. Estimated planetary
A indices were 43, 24, 11, 18, 20, 11, and 7, with a mean of 19.1.
Estimated mid-latitude A indices were 30, 20, 8, 13, 12, 10, and 5,
with a mean of 14.