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Re: (meteorobs) "Electrophonic" Fireball sound nonsense
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.
Finally, it's worth noting that our personal meteor detectors (eyes and
ears) are connected to the human brain, an instrument that filters our
experience. Perhaps we ignore swishing sounds experienced while driving by
a power line hanging across a busy freeway, but notice swishing sounds that
accompany fireballs we see from the countryside.
It's a mystery!
At 06:57 PM 8/14/2002 -0400, you wrote:
>From: Michael Linnolt <mlinnolt@alum.mitdot edu>
>To: meteorobs@atmob.org
>Subject: Re: (meteorobs) "Electrophonic" Fireball sound nonsense
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