In Ham radio there are those that bounce their morse code signals off
the ionized trail left for a few moments in the atmosphere in the
trail of an incoming meteor. It sounds like you are recording the
radio of distant broadcasts that bounce off the same meteor trails.
In a way it's like someone running down a narrow canyon yelling. As
the person is recorded, the echos of his voice off the canyon walls
document the presence of the canyon walls. It's not really the canyon
walls that are recorded but the echo proves their presence. So, I
suppose you're not really recording meteors but documenting their
presence as radio waves bounce off their trails. Very cool.
Thanks for sharing this interesting twist on nature recording with us.
Kevin
On Dec 15, 2008, at 9:46 AM, Thomas Ashcraft wrote:
> Kevin Colver wrote:
> > Thomas,
> > Not off topic at all, what an interesting nature recording! There is
> > a very musical quality to the sounds. Can you share with us how
> these
> > sounds are captured and recorded?
> > Kevin Colver
> >
> >
> >
> Kevin and all,
>
> The radio observation method used for meteors is called "forward
> scatter
> ". It is somewhat difficult to explain so I will give you a link for
> an
> overview of the method.
> .
> http://www.imo.net/radio
> .
> In essence, I am using ionization reflections off of far distant tv
> video carrier waves that are created when a meteor collides with
> Earth's
> atmosphere. It is sort of a poor man's radar but it works with high
> definition. If I can answer any questions off-list regarding the
> method
> I will be happy to. I also made an innovation by merging my radio
> array
> with an experimental all-sky video camera that has been supplied to me
> by Sandia National Laboratories. So I am capturing visual fireballs
> with
> their unique scatter reflections.
>
> I do all this work with "nature recording" in mind.
>
> On a feathery nature note: I am looking for an ID for a certain owl
> that
> landed atop the dome of my camera last full moon. There is a .mp4
> movie
> at the below link. If you are into birds then you might like this
> little
> video clip.
> http://www.heliotown.com/Owl/Visitation.html
>
> Best regards,
> Thomas Ashcraft
> New Mexico
>
>
>
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