(meteorobs) What would cause this?

[CheekyGeek]

Source:http://www.amsmeteors.org/radio/ams203.txt

"Very infrequently, the rapidly descending tonal pitch
"whistle" or "whoop" of a meteor head echo can be heard.  This is
caused by the compressed and rapidly expanding ionization around
the meteor head itself reflecting doppler shifted radio waves as
the meteor descends through the atmosphere.  Occasionally, the
meteor head echo will be accompanied by a loud underdense "ping" or
overdense "bong" as the meteor head reaches the first fresnel zone
and causes a specular reflection as well as a meteor head
reflection.  The first fresnel zone is, roughly speaking, the
primary point at which the meteor trail meets the requirements of
forward-scatter geometry for a particular system.  Those
participants desiring further explanations should consult the lists
in the appendices."

Curious where you are located and the time that this occurred. (Just
wondering if it is possibly related the Texas Panhandle event
mentioned in another thread.)

Respectfully,
Darren Addy
Alda, NE

On Sat, Jun 27, 2015 at 9:25 AM, Michael Boschat <andromed at dal.ca> wrote:

>  Hi:
>
>
>  Listening to meteors on 77.251 MHz  - Ch. 5  TV analogue.  picking up
> good rates on this frequency last few weeks.
>
>
>  anyway, a minute ago I heard a "falling bomb whistle" like  sound, it
> made a curve on the Spectrum lab plot...
>
>
>  any ideas what would have caused it?
>
>
>
>   Clear skies
> ----------
> Michael Boschat
> Halifax Center - Royal Astronomical Society of Canada
> Astronomy page:  http://www.chebucto.ns.ca/~aa063
>
>
> _______________________________________________
> meteorobs mailing list
> meteorobs at meteorobs.org
> http://lists.meteorobs.org/mailman/listinfo/meteorobs
>
>


-- 
"It's your life. You don't know how long it's gonna last, but you know it
doesn't end well. You've gotta move forward. . . as soon as you figure out
what that means."
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.meteorobs.org/pipermail/meteorobs/attachments/20150627/f756af38/attachment.html