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Re: Snakes and meteors (was Re: (meteorobs) Star Chart)



In a message dated 98-09-29 05:04:11 EDT, you write:

<< 
 I'm wondering what the average "dead time" is these days.....  <<

Dave,
My average dead time for plotting and recording meteor info is 30
seconds/meteor. Since I operate at least two cameras while observing, I
accumulate dead time from film advancing, polar alignment each time and re
positioning the rotating shutter. I advance the film roughly once every 30
minutes for dark nights. My dead time for doing this varies each time from 1
to 3 minutes. I record the start/stop times and later when I make up my report
I determine how long the dead time was for that period. The average is usually
about 2 minutes though. 

Dave>>Speaking of
 averages, what is the average size of your typical nightly meteor prior to
 atmospheric entry?
  >>

First you have to determine what magnitude of meteor is considered "typical".
There are more smaller meteors than the next size larger. For me I plot more
+2 magnitude meteors than anything else it seems. So, for +2 magnitude meteors
when they were meteoroids, I guess their size is something near that of a
grain of sand. Velocity has something to do with brightness however. The
faster a meteor is, the more energy it has when it encounters the atmosphere.
Thus a particle will seem a little brighter. But I think you will be safe to
think of +2 meteors as being about sand grain size.
George Zay

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