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(meteorobs) Re: Limits of IMO LM charts?

Lew Gramer wrote:

>> I have a very specific QUESTION about the IMO Limiting Magnitude
>> Chart #8, in Taurus. The question is, what do I do with a star count 
>> which significantly exceeds the published limit of 32 stars??

I haven't got a direct answer to your question, maybe this is to some help:

I try always to measure the Lm in two or three areas.  I usually do this
at the beginning of an observation.  In the midst of the observation, I
often stick to one counting area to save time, especially if the sky
darkness hasn't changed.  My perception for meteors goes down drastically
when I count stars, therefore I try to spend as little time as possible
on this activity.

I usually recount the Lm two or three times.  In case of discrepancy,
I note down all measurements, and find an average after the observation.

It is often difficult to determine whether stars on the border of the
area should be included or not.  This problem becomes larger at better
Lm-values (more and more stars on the border).  I think the Taurus-area
is on the difficult side, since the triangle-shaped area is very "long".
So I always try to measure the Lm in Gemini and Perseus as well, but
of course only if the sky darkness doesn't differ by a notable amount.

It is possible that the IMO-areas have been derived from AAVSO-charts.
In that case you can try to find the magnitude of the "38th brightest
star" yourself.  It's a dirty job, but someone's got to do it...  :-)

All the best,
Trond


P.S. With that kind of limiting magnitude, you should go for Neptune
sometime.  My personal record is about 7.1, and I was _really_ proud
to achieve that one.
Is it easy to see the Milky Way near Sirius from your place?  I saw
it once when it was ~5 degrees above the horizon.  (Made me proud to
see it at all, since I live on latitude 60.)
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