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Re: Lyrids and Meteorite Fall Statistics

In a message dated 98-04-19 12:13:24 EDT, you write:

bernd<< Thus, I do think -
 as O.R. Norton does - that we may be moving through a more densely
 populated area of meteoroids during the summer months. >>

This appears so from meteor observation reports. The sporadic rates jump up
quite high from about mid july to roughly mid january. 

As for Fireball rates, there are 3 times the rate during the Vernal equinox
period than the autumnal equinox period in the Northern Hemisphere. This was
proven by Juergen Rendtel and Andre Knofel for visual and photographic falls
from data acquired at the German Meteor Photographic network and the European
Meteor Photographic Network for the last 20 and 30 years respectively. Around
the Vernal equinox, the antapex is in the Zenith during the early evening.
This favors successful meteorite dropping fireballs. This is why we can expect
a greater number of fireballs in spring time than in autumn for sites north of
the equator. Bright fireballs should be more frequent in the southern spring
when the antapex reaches it's southernmost and highest point in the evening
sky. But it doesn't. It is for this reason that it is believed that the
distribution of meteroids is not isotropic along the earth's orbit. 
George Zay