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Re: (meteorobs) Angular velocities


lew>>I think Malcolm's point needs to be restated, as there is apparently
some confusion as to what he was saying?<<

malcolm>>"Likewise there is the plotting uncertainty which broadens this 
spread,
and gives rise to a lateral probability distribution. Without the speed
you just have a fuzzy great circle."<<

I believe he is essentially saying that let's say you have several typically 
plotted meteors. When plotting, it is typical to be not totally accurate in 
their alignment.  So if these several plotted meteors are traced back,  they 
may loosely intersect producing a rather broad area of suspicion. But if some 
kind of speed wasn't recorded for them, you would have no way of knowing what 
meteors are related and what are not. You will essentially end up with a 
useless wide region wondering  if they are actually related or not? You won't 
be able to narrow the radiant, if present, any tighter.  If the meteors were 
assigned a speed scale number or an angular velocity, you will be able to 
make some kind of determination as to their relationship to each other.

lew>>Again, the intersection of one's plot paths gives a rough approximation
as to a radiant point: however without angular speeds, it is impossible
to IMPROVE on this using the speed-elevation-radiant-distance relation.<<

Maybe not improve, but speed scale numbers can equal.  I've done it fairly 
often when checking out unknown intersections. The method works with known 
minor shower radiants quite well....why won't it work for a suspicious area 
of intersecting sporadics?

lew>>In effect, you'd end up having to ASSUME where the radiant lies - based
on a mere handful of possibly "sporadic-polluted" path alignments - in
order to make this same (circular) estimate based on the 1-5 Scale.<<

A radiant position would be assumed the same way for meteors that had speed 
scale assignments as would angular estimates....by noting 
speed-elevation-radiant-distance relation.  There will be no difference in 
this regards from either method. 

lew>>Again, though - and *ESPECIALLY* for beginning observers - George Zay
makes a good point that "the simpler the data gathering method for the
observer, the better". The key is to not make the method too simple to
gather needed data. <<

There are limits as to what can be gained from visually observing meteors and 
there is no need trying to be more accurate than what can be ultimately 
gained. The key is to gather data as simply as possible as long as there 
aren't any diminishing returns in the end. Making data gathering too 
complicated for any additional good is just as bad as gathering inadequate 
data than renders everything else useless.
GeoZay
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