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Re: (meteorobs) "Electrophonic" Fireball sound nonsense

Well, I believe the 0.003uW/cm^2 RF background includes all frequencies. Certainly, there are many powerful VLF transmitters around the world. I see about 60 of them listed below 30khz in one list, and WWVB the NIST time standard broadcasts 50Kw on 60khz, which creates a strong enough field by itself to allow "atomic" wristwatches to sync up all over the continental US using just the wristband as an antenna. In fact, I suspect residents in Fort Collins, CO would be exposed to greater VLF fields than even a "beamed" field from a meteor plasma, as Keay proposes. But, I havent heard of reports of strange electrophonics from that city, or anywhere else near one of these powerful VLF sources. I don't think the plasma instabilities in a meteor wake would be sufficient to produce ERP's of gigawatts, which would be necessary (at 60km) to match the strong local VLF ambients in many areas. 

--- "Dr. Tony Phillips" <phillips@spacescience.com> wrote:
> Hi Mike,
> 
> You noted that the ambient RF power we experience
> every day is about an 
> order of magnitude greater than that radiated from a
> single distant 
> fireball.  That comparison might be misleading
> because of the frequencies 
> involved. The ambient RF we experience
> everyday--like 900 MHz from cordless 
> phones--is not the sort of VLF (very low frequency,
> few-kHz) radiation 
> advocated by, e.g., Colin Keay as the cause of
> meteor sounds.
> 
> Furthermore, VLF waves from plasma instabilities
> (which Keay says form in 
> the wake of fireballs) can be beamed. This happens,
> for instance, in 
> Jupiter's magnetosphere where plasma instabilities
> in the auroral zones 
> create conical emission beams that sometimes sweep
> past Earth, causing 
> outbursts of ~18 MHz radiation that HAMs can easily
> detect at 
> home.  Perhaps such beaming of waves from meteors
> enhances the local power 
> available to drive electrophonic sounds.
>
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