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Re: (meteorobs) "Electrophonic" Fireball sound nonsense
I too was originally very skeptical of reports of sounds associated with
meteors; I figured they were just mental effects -- you see something big,
you expect to hear something, too, so your brain plugs in a sound. However,
I have seen enough plausible hypotheses that I am now unwilling to dismiss
the possibility that there is a real physical phenomenon here.
A big fireball enters the earth's atmosphere with 1 gram of mass and a
velocity of 100 km/sec -- that yields 10**7 Joules of energy, which if
released in one second, is a power of 10**7 watts. Very rough calculations
indicate that at least half of that power goes out as light, but that still
leaves several million watts going somewhere else. I don't know the
magnitudes of the various energy release mechanisms, but I am willing to
accept the claim that there's plenty of energy unaccounted for that could
end up as low-frequency EMR. Moreover, the interaction of the meteor trail,
a large moving conductor, with the earth's magnetic field, should generate
some interesting radiation, much of which might be anisotropic, or at least
polarized. What I find particularly interesting is the possibility of very
very low frequency radiation -- at audio frequencies. The wavelength of such
radiation, roughly 10**5 meters, just happens to fall in the same ballpark
as the length of the meteor's trail.
As to your calculations about background levels, I agree that the first part
of your argument is powerful. However, your calculations show a S/N of .1,
which actually isn't that hard to detect, and the additional factors that I
have pointed out might well bring that S/N up at least an order of
magnitude.
This is all just speculation on my part. But it's difficult for me to
dismiss such speculations out of hand. The numbers we have aren't solid
enough to permit sweeping conclusions. I remain skeptical, but I will
withhold judgment until I have seen better data addressing some of these
oddball hypotheses.
Chris Crawford
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