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Re: (meteorobs) Observing the Arietids-Triangulids



In a message dated 96-08-22 10:57:21 EDT, you write:

<< First, of all the fourth magnitude meteor was hypothesized based on my 
 observing conditions. I have seen a very small percentage of 5th-magnitude 
 meteors during 23 years of observing, because of my typical limiting
magnitude 
 of 5.5-6. A quick check through my observing logs reveals that the 
 5th-magnitude meteors were all apparently seen when they were directly in my

 line of sight. So, instead of saying 4th-magnitude meteors while I was at
work 
 yesterday, I will revise that number to 5th-magnitude after checking my logs

 this morning. For you it might be 6th-magnitude meteors. It really does not 
 matter. The fact is a faint meteor in any observer's observing conditions is

 more difficult to see when not directly in your line of sight. 
  >>
-----
Gary, 
I don't disagree with this.  I was with the understanding that you said the
meteors from this possible radiant were for the most part dim. if they are
that close to your Limiting Magnitude, looking at the radiant area will
produce very short and not so sure meteor sightings. If you were out a lttle
ways...about 30 degrees from the suspected radiant region, you will still
need to be looking just about at the right spot for a dim meteor to become
apparent...but their overall movement will be longer in travel distance which
would increase the effective area of detecting these barely detectable
magnitudes. 
---------

>>Second, the "10 degree" length was a bad choice on my part, but then I
never 
said just how far it was from the radiant now did I?  :-) Nevertheless it is 
still much shorter than the long-trailed meteor, so it basically comes down
to 
personal terminology. The number could easily be decreased to a degree or
two. 
The fact still stands that it is easier to see a faint meteor when closer to 
the radiant because of the foreshortening of the path. Basically it comes
down 
to more photons gathering on the cones within your eye. If you are looking at
a 
radiant, meteors from that radiant would more likely be in your line of sight

and very accurate plotting and, subsequently, the precise location of the 
radiant would be better noted. This region of the sky is interesting because
a 
slight drift in the declination has some very interesting effects on the 
orbital inclination of the stream. To everyone I need to emphasize, WE NEED
TO 
VERY PRECISELY DETERMINE THIS RADIANT. (Remember, this is emphasizing, NOT 
yelling   :-)   ). 
-------
Well Gary, a non- fireball type meteor that had a length of 10 degrees
implies that it was viewed at least 20  degrees from the radiant if the
radiant was over 30 degrees above the horizon.  Most meteors I record are 10
degrees long or less...the few exceptions are the apparent earth grazers or
fireballs...and of course a few intermediates are thrown in to indicate that
they came from a distant radiant as well. If you saw a 20 degree long non
-fireball meteor, this would indicate that it is at least 60 degrees from a
radiant.  
I still disagree on your insistence that you can get a very accurate plot
with very short meteors...unless you get a lot of them...but this isn't
apparently one of those showers where you are going to have a lot to work
with or it would have been picked up a long time ago and chiseled in stone.
If the meteors were bright and produced trains...but as indicated in Sky and
Tel, the velocity of these are suppose to be somewhat medium...non train
producers to give you a moment to accurately notice it's travel alignment. If
the meteor becomes brighter because of foreshortening and makes it more
apparent, the short movement isn't easily noticeable to detect subtle
directions.  Also, accurate start points are not that frequent and if you are
off just a little on your plot, being that close to a radiant, you can have
the meteor appear to be pointing towards the radiant rather than from it. 
George Z.