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Re: IN SYMPATHY to the Hale-Bopp Cooperative

Article: <5fmo6j$>
From: )
Subject: Re: IN SYMPATHY to the Hale-Bopp Cooperative
Date: 6 Mar 1997 15:34:43 GMT

In article <5fi4uj$> Jim Scotti writes:
>> (Begin ZetaTalk[TM])
>> Find, now since you claim that the Orbital Elements are
>> changed as a result of OBSERVATIONS, please tell us
>> what observation caused the eccentricity of the mythical
>> Hale-Bopp to change from
>> 0.995038361 on May 28, '96 to
>> 0.995072729 on June 27, '96,
>> as announced by JPL. Lest you say this was due to
>> perturbations upon the recent passage of Jupiter, where
>> as we have been stating the posted observations of
>> Hale-Bopp had it leaping AWAY from Jupiter upon passage
>> of that giant, other than the fact that this adjustment moved
>> the mythical Hale-Bopp closer to an occultation with
>> Gamma Andromedae, what would be an effect on the
>> ellipse of a passing comet that would TIGHTEN THE
> Marsden's first elliptical orbit published on MPEC 1995-P02)
> dated 1995 August 2 lists the following elements based on 248
> observations between 1993 Apr 27 and 1995 August 2 (I'll use
> the same symbols used in your post of Yeomans latest
> elements): ...
> The differences are significant, but since they both include
> the 1993 McNaught observation, they are surprisingly close
> together. Now, if we use the elements Marsden published on
> IAUC 6191 which do not include the 1993 observation and
> are assumed parabolic with an arc of 1995 July 24 through
> July 26 with only 57 observations, the elements are given
> as: ...
> They just barely resemble the most recently computed
> elements and give a position for April 1 of ...
> jscotti@LPL.Arizona.EDU (Jim Scotti)

(Begin ZetaTalk[TM])
You seem to be avoiding the dates in question, May 28, 1996 to June 27, 1996. Why is that? We get detailed descriptions of changes between April 27, 1993 and August 2, 1995, and then detailed descriptions of changes between July 24, 1995 and July 26, 1995, but NOT THE DATES IN QUESTION! Please address the issue. If Hale-Bopp was observed to be where it was on May 28, 1996, at Dec -15, and then was observed a month later to be at a position of Dec -12, placing it at Dec -12 on May 28, 1996, then WHAT OBSERVATION CAUSED THAT CHANGE? This is a paper perturbation AWAY from Jupiter!

Where widening the ellipse in this way would widen, not tighten, the eccentricity, a contradiction was built into the new Orbital Elements showing that the eccentricity had TIGHTENED. These two illogical changes to the orbit, on paper, allowed the orbit at that time to place the mythical Hale-Bopp closer, a giant step closer, to an occultation with Gamma Andromedae at perihelion. A step, we might add, that was reversed after we pointed out this continuing gambit being played with the paper orbit of Hale-Bopp.
(End ZetaTalk[TM])