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(meteorobs) Observing Before Midnight



Mark Davis wrote:


"I agree with you Wayne. In addition to the fireball lure, there is also
little data available (that I am aware of) on year round, early evening,
sporadic rates. This might prove of interest to a future researcher...."

Thank you, Mark.  In studying the sporadic meteor background using visual
data, it is important to have as much coverage through the night as
possible:  from dusk to dawn, and expecially on those non-shower nights.
Statistically speaking, it is desirable to maximize your sampling time, in
order to detect the trends and fluctuations which occur during the time
that meteors are visible.  Limiting your sample to only those few hours
when rates are highest would give only a narrow, skewed picture of the whole.

In picking up the AMS investigation of the sporadic flux once again, we
find that our visual database is, as one might predict, skewed heavily
toward the pre-dawn hours on the days around major shower maxima --
especially the Perseids.  It is rather difficult to drum up a "campaign"
for those "magnificent" 2-4 meteors per hour on a cool evening in March.
Add to this the fact that the endurance limit for most visual observers is
generally about 4-6 hours, causing them to shift their "window" toward the
periods of greatest activity after midnight.  This bias in the visual data
is one of the reasons we have began the sporadic study using the
radiometeor data first, with the visual input to come second.

BTW, I cannot say that I was much better as a visual observer myself, as
most of my observing sessions began around midnight, although sometimes
stretching back to 9 or 10 pm local time.  Just for the fun of it, I would
try to do one or two "dusk to dawn" observing sessions in late June or
early July, when the night was at its shortest, but this was an exception.  

Keep at it, Jonathan!  I fell in love with astronomy at a early age as
well, and bought my first 3-inch Newtonian reflector at age 12.  On school
nights I had to be in by 9 pm, but on Friday and Saturday nights I had free
reign of my back yard as late as I could stand it -- provided that I could
still mow lawns and weed flower beds the following day.  The meteors were
not taken very seriously then, but if you look in my old copy of H.A. Rey's
"The Stars" you can still find a few sketched in Perseid plots on the
appropriate sky chart (albeit, not a gnomonic projection).  My 10 year old
daughter has this book now.

My how time flies...


Take care,

     Jim


James Richardson
Graceville, Florida
richardson@digitalexp.com

Operations Manager / Radiometeor Project Coordinator
American Meteor Society (AMS)
http://www.serve.com/meteors/


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