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Re: (meteorobs) Fw: [MIAC-L] re simultaneous meteor sounds.




How unusual that this particular topic stirs such extraordinary passions.
(And there are clearly passions - in addition to the well-stated scientific
arguments - present in that last forward from Dr. Tatum!) I wonder why??

In any case, I enjoyed much of Dr. Tatum's post, although I did find the
following passage rather unfathomable - and also unworkable, considering
that MOST bright meteor observations (whatever you may call them) are not
simultaneously photographed - so their provenance is rarely verifiable:

> I also feel that the word "fireball" should not be used (notwithstanding
> the IAU definition) for shower meteors of cometary origin.  Meteors
> brighter than -4 can be seen any night, and in any case no one can
> possibly estimate their magnitude  (The Croatian observations MEASURED
> their magnitudes.)  The word fireball should be restricted to
> genuine fireballs of asteroidal origin and are of meteorite-dropping
> potential.

In any case, perhaps Dr. Tatum can clarify for his wider audience, what is
meant by "Meteors brighter than -4 can be seen any night, and in any case
no one can possibly estimate their magnitude"? Why exactly (assuming Dr.
Tatum believes a visual observer can estimate ANY meteor magnitude) is it
possible to estimate magnitudes below -4, but not above... Is this simply
an arbitrary cutoff, due to the brightness of Venus at maximum? And if so,
then is the field of "valid" magnitude estimates limited to only -2.5, if
Venus is not in the sky but Jupiter is? Or -1.5 if we have only Sirius up
at any given moment... ?? Again, it was only the one cited paragraph that
seemed to need clarification for an (admittedly) amateur audience.


It would be interesting indeed, if the only time of the year when a shower
meteor could be reported as a "fireball" was during the activity periods of
the Geminids and delta Leonids - they of conjectured asteroidal origin! :)

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