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Re: (meteorobs) What I think I know (and don't know) ...



>Subject: Re: (meteorobs) What I think I know (and don't know) ...

Yes there have been some rather interesting replies to this problem.  
However, let us look at the most basic precept, namely the release of dust 
from a comets nucleus.  When we look at a come in passing, we can usually 
see two basic tails.  The type I or ion tail is directly influenced by solar 
radiation and pressure.  Less obvious is the radiation pressure or solar 
influence on the type II tail or the dust tail.  If we examine photos of the 
coma area where it flows into the tail, sometimes we can see no transition, 
such as with Comet Arend-Roland 1957III (C/1956R1).  It is obvious that 
there is a large quantity of dust, since the better photos clearly show the 
anti-tail.  Comet Seki-Lines 1962 III (C/1962 C1)also shows no transition.  
We can follow the dust tail all the way into the coma, with no separation.  
Yet we can also detect what appears to be areas of irregular dust 
deposition.  Halley's comet is also an example of where there has been 
uneven deposition of dust.  So was comets West 1976 VI (C/1975 V1), 
Brorsen-Metcalf 19898X (23P/1989 N1), and many others.  So if the dust is 
being ejected by the nucleus in and irregular fashion then we can expect 
areas of concentrated dust to be follow the comet in a similar and related 
orbit. During an apparition of a comet, if there should be a tail 
disconnection event (DE), it is quite possible that the may also influence 
the dust tail.  So in either case we should see areas of greatere and lesser 
concentration of dust all throughout the orbit of a comet.  Over time, these 
areas will spread out a little due to gravitational perturbations, which 
might explain why some years we see showers and some we don't.

Cheers,
Gregg

rigel_ori@hotmail.com
at OCS.


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