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(meteorobs) Leonid dust trail age vs. population index

Hi!

  It appears that it is either generally assumed (or observed) or shown by 
theoretical models that population index is in some way proportional to the 
dust trail age: the younger the trail, the higher the population index (more 
faint meteors).

  Could someone explain the major difference between 1833 and 1966 Leonid 
storms? While they were both caused by very young trails (1-rev in 1833 and 2-
rev in 1966) the apparently displayed VERY different brightness profiles (and 
to some extent activity profiles as well). Most reproductions and eyewitness 
accounts of the 1833 storm indicate it was a bright event with many spectacular 
fireballs lighting up the sky (one account says up to 20 persistent trains 
could be seen at once!) and the storm lasted fairly long - unusual meteor 
numbers were noted in the evening and the 'high' storm activity appears to have 
lasted at least from 2 to 5 a.m. (on the east coast). 1966, on the other hand 
was a time-wise narrow event with a sharp peak, dominated by faint meteors and 
very rare fireballs. Why such a difference? Is it related to processes after 
dust ejection from the cometary nucleus or could it possibly indicate a change 
in activity of the nucleus? Was there perhaps significant contribution from 
1699,1767 and 1733 trails during the 1833 storm?


  Or is it that larger particles that produce fireball meteors have smaller 
velocities relative to the cometary nucleus than the smaller particles that 
produce faint meteors and that small particles therefore dominate the outskirts 
(front and back extremities of the trail) while the large particles tend to be 
concentrated near the center of the trail and take longer to spread out. 
Therefore in 1966 we could have a similar bright peak if we hit the center of 
the trail dead-on?

Ok, now I'm way out... ...waiting for any answers.

Clear skies!

Jure A.


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