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Re: (meteorobs) A-T 1996 ZAYGE ...long article
>On Thu, 19 Sep 1996 Malcolm Currie wrote:
>
>>The 1993 observations of the A-Ts had discordant radiants according to
>>Gary's article in WGN 21:6, p.262. These were
>>
>> Kronk 35 +30
>> Sleeter 30 +30
>> Gliba 28 +19
>>
>>Gary combined these to get 30, +28, i.e. not giving much weight to
>>George's declination and his own right ascension. What was the
>>justification for this, apart from the fact that they look discrepant?
>>In which direction was George looking?
and
>>What's the evidence for a southern component?
I do not have the article with me, and I wrote several articles at that
time for different publications, but I thought I mentioned in that article
that George had said the alignment of the meteors did not favor an accurate
determination of the declination. I believe he said that measurement could
have been in error by something like 4 or 5 degrees. He was much more
confident about the right ascension because of one or two meteors that were
deading either due south or due north (I can't remember which, as I don't
have the material with me, so this is from memory). As stated in the past,
my radiant was purely a visual determination and the right ascension also
did not receive as much weight. Sleeter's radiant was actually a plot using
a combination of my meteors and his. The plotting was prompted by our
continued accidental observations of meteors around the Aries, Triangulum,
Andromeda, and Cassiopeia region. That was the region we were facing
because of deep sky observations. Another prompt for us to begin plotting
was a very nice short-trailed meteor that passed right alongside Gamma and
Beta Arietis heading southward. My declination seemed strongly defined by a
short-trailed meteor that headed right along the +30 degree declination
line. Therefore, I favored Sleeter and Gliba's right ascension and Sleeter
and my own declination. By this time I was already searching for past
appearances of the stream and the radiant of 30, +28 was obviously
supported.
Interestingly, despite George's uncertainty about his declination, there
were a few visual radiants near his more southerly radiant. Even more
interesting is that in Zdenek Sekanina's Radio Meteor Survey, a radiant
near Alpha Arietis was detected in 1969, while a radiant near Alpha
Triangulii was detected in 1962, 1963, and 1969. Please bear in mind that
Sekanina only identified the two streams from the 1969 data. My search
through the over 39,000 orbits revealed the meteors in 1962 and 1963. Could
these two radiants be part of the separation component discussed in the
last letter? Maybe the radio meteor data indicate the Alpha Triangulids are
a more dispersed stream than the Alpha Arietids. This could imply that the
latter stream is the newest filament.
Sincerely,
Gary
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