RF-Seismograph did not record any changes in the popagation

Going *strictly* by the numbers, the stations for which you had 3 or more spots one can see a 'peak' somewhere near the max of totality for the central part of the country:

2017-08-21 18:26 WB5WPA 3.594029 -26 0 EM13qc 5 W0AEW DN70je 1097 318
2017-08-21 18:16 WB5WPA 3.594030 -23 0 EM13qc 5 W0AEW DN70je 1097 318
2017-08-21 17:38 WB5WPA 3.594030 -26 0 EM13qc 5 W0AEW DN70je 1097 318

---------------------------------------

2017-08-21 18:26 KD6RF 3.594116 -26 0 EM22lm 5 W0AEW DN70je 1246 316
2017-08-21 18:18 KD6RF 3.594116 -21 0 EM22lm 5 W0AEW DN70je 1246 316
2017-08-21 17:32 KD6RF 3.594116 -23 0 EM22lm 5 W0AEW DN70je 1246 316
2017-08-21 14:46 KD6RF 3.594117 -27 0 EM22lm 5 W0AEW DN70je 1246 316

de Jim

 

ANTENNA: 1/2 wave end-fed for 80m (~134 ft) thru 9:1 unun, 10 ft coax to mfj tuner
RIG: ic-7200 (AGC off, RF gain 1/2)
PWR: 0.5 watt

 

We reached 92% of totality at ~11.40 am MDST (1740 utc), so it looks as if the D layer dissipated more quickly than when it reappeared. At least you and KD6RF were active before & after the eclipse.

My anecdotal evidence would seem to reinforce K1YOW's remarks about the similarity to grey line propagation characteristics. But as he said, many more data points will be necessary, so I'm looking forward to the results as they come in and are analyzed.

 

Because when you look at the sky during an eclipse the moon and the sun only take up a very small part of the sky!!! So unless you use a beam concentrated RF energy it just bends around it. Similar to the way shortwave bends around mountains.

Alex - VE7DXW

 

Two things here -

1) It is my observation (discovered through doing HF DF work (and reading the 'white papers' on same) that the 'path' on HF is likely _not_ the one you think it is, that is to say, the reflective or refractive 'patch' of ionized ionosphere responsible for propagation is likely _not_ midway between the two stations working but may be noticeably off to one side or the other.

2) If you viewed the linked video, I did not notice different propagation 'effects' appearing until about 1809z here in north central Texas.



de Jim

 

Alex, I agree that the sun and moon are very small parts of the observable sky - but what does that have to do with localized effects of a shadow? We are basically looking at what I call a very localized gray line effect - the D and E layers degrade and reform quickly, but at different rates and the F2 layer degrades and reforms at a slower rate. So, as was seen by most hams and professionals, when the D layer degraded quickly bands like AM broadcast, 80 and 40 got better - less absorption, as expected. Other hams and professionals saw the F2 decline, and the Millstone Radar showed that there was a two fold electron loss, so, 20 meter signals declined in strength. As small as the moon is, it looks like its shadow was big enough to affect the ionosphere's local absorption and reflection layers, similar to a gray line. The gray line is also small (thin) and is roughly one hour wide with effects varying plus or minus 15-20 minutes in that zone, depending upon conditions. Looking at many of the reports received and the comments here in this note, it looked like the moon's small shadow was enough to affect the local ionosphere and radio signals through it. Joe, K1YOW

 

The other issue was the fact that we had a very strong interfering sun spot that raised the background radiation and the solar flux. This made the D-Layer a lot thicker at the time of the eclipse and it attenuated the lower bands to the point where they would show any propagation. In our RF-Seismograph reading and measurement we have propagation at 160, 80 and 40 until the sun comes up builds the D-Layer with all this extra energy and nothing gets through.

Alex

 

Here are a couple of the more noteworthy sets of WSPR spots from stations in/near the path of totality -

No observed 'effect' that I can tell ... /sarc

2017-08-21 19:58 AC0G 3.594036 -18 0 EM38ww 5 K9AN EN50wc 367 68
2017-08-21 19:42 AC0G 3.594036 -21 0 EM38ww 5 K9AN EN50wc 367 68
2017-08-21 19:28 AC0G 3.594036 -26 0 EM38ww 5 K9AN EN50wc 367 68
2017-08-21 18:44 AC0G 3.594036 -6 0 EM38ww 5 K9AN EN50wc 367 68
2017-08-21 18:28 AC0G 3.594036 -11 -1 EM38ww 5 K9AN EN50wc 367 68
2017-08-21 18:22 AC0G 3.594036 -4 1 EM38ww 5 K9AN EN50wc 367 68
2017-08-21 17:48 AC0G 3.594035 -18 0 EM38ww 5 K9AN EN50wc 367 68
2017-08-21 17:42 AC0G 3.594036 -20 0 EM38ww 5 K9AN EN50wc 367 68
2017-08-21 17:36 AC0G 3.594036 -29 0 EM38ww 5 K9AN EN50wc 367 68
2017-08-21 17:02 AC0G 3.594036 -25 0 EM38ww 5 K9AN EN50wc 367 68

2017-08-21 22:36 WB5WPA 3.594023 -22 0 EM13qc 5 AC0G EM38ww 764 31
2017-08-21 22:22 WB5WPA 3.594023 -22 0 EM13qc 5 AC0G EM38ww 764 31
2017-08-21 21:42 WB5WPA 3.594023 -19 0 EM13qc 5 AC0G EM38ww 764 31
2017-08-21 18:16 WB5WPA 3.594024 -14 0 EM13qc 5 AC0G EM38ww 764 31
2017-08-21 18:12 WB5WPA 3.594023 -17 0 EM13qc 5 AC0G EM38ww 764 31
2017-08-21 16:02 WB5WPA 3.594023 -29 0 EM13qc 5 AC0G EM38ww 764 31
2017-08-21 15:34 WB5WPA 3.594023 -24 0 EM13qc 5 AC0G EM38ww 764 31

2017-08-21 22:32 AC0G 3.594039 -26 0 EM38ww 5 WB5WPA EM13qc 764 213
2017-08-21 22:16 AC0G 3.594039 -24 -1 EM38ww 5 WB5WPA EM13qc 764 213
2017-08-21 18:44 AC0G 3.594039 -22 0 EM38ww 5 WB5WPA EM13qc 764 213
2017-08-21 18:28 AC0G 3.594040 -17 0 EM38ww 5 WB5WPA EM13qc 764 213
2017-08-21 18:22 AC0G 3.594039 -15 0 EM38ww 5 WB5WPA EM13qc 764 213
2017-08-21 17:48 AC0G 3.594039 -24 0 EM38ww 5 WB5WPA EM13qc 764 213
2017-08-21 17:42 AC0G 3.594039 -28 1 EM38ww 5 WB5WPA EM13qc 764 213

AC0G was in the path of totality I think in Missouri

de Jim

 

One of the more interesting sets of WSPR data for 160 meters from a couple of Texas stations

2017-08-21 19:22 KD6RF 1.838126 -20 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 19:14 KD6RF 1.838127 -25 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 19:04 KD6RF 1.838127 -29 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 19:00 KD6RF 1.838127 -22 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 18:56 KD6RF 1.838127 -14 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 18:42 KD6RF 1.838127 -15 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 18:34 KD6RF 1.838128 -13 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 18:26 KD6RF 1.838128 -9 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 18:20 KD6RF 1.838128 -11 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 18:12 KD6RF 1.838128 -19 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 17:36 KD6RF 1.838127 -15 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 17:28 KD6RF 1.838127 -22 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 17:12 KD6RF 1.838125 -17 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 16:54 KD6RF 1.838128 -26 0 EM22lm 5 KM5HM EM21 116 180
2017-08-21 16:40 KD6RF 1.838128 -23 0 EM22lm 5 KM5HM EM21 116 180

2017-08-21 18:56 K5KJ 1.838018 -14 0 EM12 10 KM5HM EM21 219 120
2017-08-21 18:32 K5KJ 1.838020 -6 0 EM12 10 KM5HM EM21 219 120
2017-08-21 18:20 K5KJ 1.838020 -8 0 EM12 10 KM5HM EM21 219 120
2017-08-21 17:54 K5KJ 1.838019 -23 0 EM12 10 KM5HM EM21 219 120
2017-08-21 17:12 K5KJ 1.838017 -17 0 EM12 10 KM5HM EM21 219 120
2017-08-21 16:54 K5KJ 1.838020 -22 0 EM12 10 KM5HM EM21 219 120
2017-08-21 16:46 K5KJ 1.838019 -22 0 EM12 10 KM5HM EM21 219 120
2017-08-21 16:38 K5KJ 1.838019 -22 0 EM12 10 KM5HM EM21 219 120
2017-08-21 16:10 K5KJ 1.838018 -15 0 EM12 10 KM5HM EM21 219 120
2017-08-21 15:14 K5KJ 1.838016 -14 0 EM12 10 KM5HM EM21 219 120

 

the bands were dead all day here ... made 4 contacts

 

The high solar activity was definitely not helping...

Alex

 

This is my eperience on 80m. Started up wspr about 3 hours before max coverage (98.5% in my area) I had s9 noise and no one was hearing my signal. Suddenly about 15 minutes before eclipse noise dropped to about S3 and wspr map showed me being received in tennesee. Then as the eclipse progressed to the southeast was received by more and more stations to the South and East. Some long after my noise increased to s9 again.

 

First of all, Alex, your math is wrong (50 km * pi = 157 km^2...should be (50 km)^2*pi or whatever value you're using for the radius) on the area of the umbra, but that's neither here nor there because it won't affect the substance of the argument much.

As many posters have pointed out, there was an observable effect in the ionosphere for this eclipse (and virtually every other eclipse in the era of radio science) and I would simply suggest that your RF Seismograph does not observe the relevant quantities (although it may observe/measure other interesting and relevant quantities). That being said, I want to not confuse that fact with the fundamental ionospheric physics which have been well-known for 70 years or so at this point. There's a simple (differential, although I'm writing it in words for this audience) equation that describes how much plasma there is at any point in the ionosphere:

change in electron density = production - loss + transport

For the purpose of this discussion, I'm not going to discuss transport (plasma that moves into an area from somewhere else by diffusion, electrodynamic drifts, winds, etc); although transport is important during an eclipse, the details would add unnecessary complication to this discussion. So, now we're talking about this version of the continuity equation:

change in electron density = production - loss

As Joe, K1YOW, rightly pointed out, the lifetimes of plasma in D, E, and F1 regions are relatively short, 10s of seconds or less. So, if you completely "turn off" (make it zero) production by turning off the solar illumination, the continuity equation becomes:

change in electron density = -loss

That is the situation we have after sunset on any given day. And, it is the situation we have in the (as you rightly pointed out) very localized region of the umbra. But, as I said above, it only takes a few tens of seconds for the bottom part of the ionosphere to recombine away. When you have "two minutes and 37 seconds of totality" or whatever people were chanting, that's plenty of time to create a hole or cave in the bottomside.

However...there's more. The production is a complicated function of (solar) EUV illumination, neutral (atmospheric) density profiles, zenith angle, and so on. For any given day and location there are always times at which production is insufficient to overcome loss (and transport) even under sunlit conditions, and especially in the lower ionosphere which affects HF propagation. Even partial obscuration of the sun by the moon, as we saw over a continental scale in this eclipse, modifies the EUV input considerably (analogous to increasing the solar zenith angle, that is, lowering the sun on the horizon) and will reduce the plasma density. This partial obscuration lasted for several hours at many locations and created a depression in the electron densities over the entire continent during that time. I think that was clearly borne out in observations (even some posted in this thread).

The point of me writing this is to respectfully suggest that you revisit your analysis of the situation:

1. Decades of peer-reviewed research have established what I described above to the point that it's in all the standard textbooks (Schunk and Nagy's Ionospheres for the hard-core scientists, Tascione's Introduction to the Space Environment is a more tractable text for the technically-literate nonspecialist; and there are many others) on the topic.

2. We do not know if your RF Seismograph is even capable of observing the types of effects one would expect from the established physical expectation of the eclipse. Again, I stress that this doesn't mean it can't make useful observations of the ionosphere or radio environment, just that it doesn't capture the eclipse effects. Perhaps reprocessing your data will make it clearer?

3. Instead of inventing new physical explanations for why you did not observe an effect, it seems to me that it would be more profitable to ask why in the context of everything that is known first.

 

Here are the spots I find in the WSPR database with four or more spots from the same reporting station -

(ascending time order from top to bottom on these)

2017-08-21 17:36 KD0YTE 3.574003 -21 0 EN30qf 10 KC5LT EM86ci 883 116
2017-08-21 17:50 KD0YTE 3.574003 -22 0 EN30qf 10 KC5LT EM86ci 883 116
2017-08-21 18:22 KD0YTE 3.574003 -9 0 EN30qf 20 KC5LT EM86ci 883 116
2017-08-21 18:32 KD0YTE 3.574003 -10 0 EN30qf 20 KC5LT EM86ci 883 116
2017-08-21 18:36 KD0YTE 3.574004 -10 0 EN30qf 20 KC5LT EM86ci 883 116

2017-08-21 18:12 KD0YTE 3.573999 -25 0 EN30qf 20 N4WD EM74iw 873 130
2017-08-21 18:22 KD0YTE 3.573998 -22 0 EN30qf 20 N4WD EM74iw 873 130
2017-08-21 18:42 KD0YTE 3.573999 -22 0 EN30qf 20 N4WD EM74iw 873 130
2017-08-21 18:32 KD0YTE 3.573998 -19 0 EN30qf 20 N4WD EM74iw 873 130

2017-08-21 18:18 KD0YTE 3.573999 -23 0 EN30qf 20 K7DR EN82ln 840 69
2017-08-21 18:22 KD0YTE 3.574000 -18 0 EN30qf 20 K7DR EN82ln 840 69
2017-08-21 18:32 KD0YTE 3.574001 -21 0 EN30qf 20 K7DR EN82ln 840 69
2017-08-21 18:36 KD0YTE 3.574001 -29 0 EN30qf 20 K7DR EN82ln 840 69

de Jim

 

WSPR log files can be uploaded directly to the server. There are instructions/a user interface on the "old" database page and the link to that is at the bottom of the usual database page.