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Longitude/time




In reference to Normans determining the exact time by one's longitude.  I use
to do that myself, but stopped when I discovered that IMO does it
automatically when it gets entered into the computer. There's no need for
NAMN people to worry about this unless you really want to go thru all the
headaches of figuring it out each time. If one does so, it's for their own
personal use...otherwise it's redundant. 

I personally record each meteor by hour and minute.  It may be a short cut
for Norman, but you never know where the time will be important for some
other studies...namely clues to meteor clumping and possibly areas one hasn't
thought of yet...or may mean something to some one else's future studies? If
rates were very high, yes leave out hour and minute for each meteor.  But I'd
enter times a little more frequent than at half hour intervals...say maybe 10
or 15 minutes. For meteors of 0 magnitude or brighter, I try to record the
nearest second due to my camera operations...just in case I capture it
photographically...that is those that are are even remotely possible of being
in my camera's field of view. I really perk up when negative magnitudes seem
to cross my camera's field. 

As to the 1995 Eta Aquarids...I had a very extensive campaign with them that
year.  I recorded data on 10 nights.  However, 6 nights were during the peak
active nights and we were plagued by fog on some nights. There were 5 of us
on some of the peak nights...Lunsford, Arlt, Rendtel, Holman and myself. I
recall being the low man...as usual with 15 Eta's /2.5 hour period was my
highest.  The others recorded their highest I believe in the neighborhood of
about 15 to perhaps near 20 for the same periods. Figuring that my latitude
is nearly 33 degree north, our rates were probably comparable to
Normans...possibly higher ZHR's for us if you take into consideration that my
sky LM was probably near 6.0 for me and about 6.5 for the others. I'm
assuming that Norman had his usual 7.0 plus LM.

Some of the problems that people make in converting their data into ZHR's is
that they are often determined from less than desirable conditions...that is
cloud coverage for example.  I've seen ZHR's figured from skies with 75 % sky
coverage.  I believe it was the 1993 Perseids along the eastern U.S. coast
that produced some ZHR's that were in the 700's?  I believe sky and telescope
published some of these high ZHR's shortly afterwards.  It may have not been
the 1993 Perseids, but I believe it was.  I believe nearly the whole east
coast was suffering from lousy weather then. Anybody here had clear skies for
the 1993 Perseids? If so...where were you? 

As to Norman's Twilight Quadrantid.  I guess it is possible to see it coming
from the setting side rather than the rising?  How far below the horizon
would that make the radiant be for around 6:45pm at latitude 28 degrees?  I
have seen several Perseids each year just as it begins to get dark...but the
radiant is pushing along the horizon then. Meteors sighted when the radiant
is along the horizon is fun to watch.  they are so long and creates a lot of
excitement. 
George