The signal bursts in the US signals are almost certainly the result of glancing specular reflections from gravity wave fronts in at least one, and probably two or three Es clouds.
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| Audacity audio spectrum plot of Es bursts. |
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| NLC can be considered visual manifestations of Es. Light 'bursts' are seen in the highly reflective regions where sun-cloud-observer path lines up perfectly. The same happens with the TX-Es-RX path of VHF radio. |
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| Argo visual plot of received FT8 audio of 50MHz signals, arrows showing the obvious pulses. The brightest pulse on top left appears half way through a FT8 cycle from virtually nowhere, peaking 40dB above background in fractions of a second. |
In a typical Facebook trolling exercise, someone unilaterally dimissied this as anything unusual, asserting it was "meteor or aircraft scatter" - but not venturing to say which. I have never heard this kind of effect happen over and over again over many hours, even during major meteor showers. Sporadic bursts, sure, but not of this quality. The problem with this explanation is that all propagation can periodically come to a stop at 6m, including the bursts. There is no good reason why sporadic meteor bursts should simultaneously stop in step with general Es.
There's no way it's aicraft scatter, because air traffic is 95% lower than normal at present, and I have never, ever heard aircraft scatter from here at 50MHz even when traffic is normal.
