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Re: (meteorobs) Leonids: max ZHR in 1966
Hello Robert,
Of course you are right: they might have had their eyes open for less
than one second, that is completely possible. The fact that we do not
know, makes clear the snag in the procedure and figure anyway. But Peter Bus
had some
of his friends try this method on flocks of birds (by lack of a meteor
storm!) and used a stopwatch to determine their actual looking time. They
all took more than one second.
Anyhow, my main point simply is that all those 'ZHR's quoted are not
ZHR's in a modern sense, and people fail to realize this. When this
would be realized, the whole discussion about the 1966 (and other year's)
rates would have a different starting point.
The point is: if we realize that the 150,000 figure has been deduced from
the visual counts in a incorrect way (as they are!), then it is
immediately clear that it makes no sense that photographic data also
(should) produce that 150,000 figure. Why should they!? Actually, they
should not!
If photography still suggests 150,000 then
this simply points out that there are indeed snags in photographic rate
determination too. The point again is, why should photographic data
confirm a
rate that is just wrong anyway? That should make you suspect indeed about
the photographic rate deduction procedure. Perhaps, there is enough room
in adjusting certain parameters that you can make the results comply to
what you want (e.g. 150,000, if you want to confirm that figure).
I never ventured into work on the 1966 photographs, and will not venture,
simply because the method is not sound. You will never get reliable rates
from photographs because too many things remain uncertain and difficult
or impossible to correct for in a meaningfull way. Somehow, it has come
into this world that photographic data provide much better insight in
ZHR's when rates are high, but from our experience, I simply want to put
that assumption to doubt.
Regards,
-Marco Langbroek
References: