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    Re: Interesting Bowditch CelNav results was : Celestial Coordinator
    From: Antoine Couëtte
    Date: 2011 Dec 9, 18:57 -0800

    RE :
    [17580] Re: Interesting Bowditch CelNav results was ...


    The Bowditch reductions were done with Pub. 229. Without running the numbers, I suspect that you did yours with the Law of Cosines, which could explain the difference.



    Dear Stan,

    Thanks for your quick comment.

    Yes, I did use direct trig computation from each individual DR position.

    Difference between computation methods here will certainly yield significantly different end results, as I have quite often observed in the past. This is one reason why - once having number crunching power at my finger tips (Thanks again to HP !!) - I totally discarted such "approximate" computations methods some 35 years ago.

    I had also thought about your suggestion as being a possible explanation for the differences found between Bowditch and own results.

    Can this difference between methods explain just by itself a 0.9 NM difference in the intercept of Spica (20.2 NM vs 22.1 NM)? Well, maybe, after all, but ...

    ... could it also "reasonably" explain a ... 6.3 NM in the intercept of Kochab (5.2 NM vs 11.5 NM) ? Would this assumption "reasonably" make sense ???

    So, it looks like I am definitely missing something here.

    Any help from any body, simply through running by himself the same computations ? (hint : the GMT date and time are in the morning of May 17, 1995).

    Thanks in advance to who-ever will bring some light here.

    Best Regards to all


    Antoine M. Couëtte

    PS : For any interested "Good Samaritan", I could publish here "rearranged" computational starting data as well as end results. Although (a bit) helpful - one never knows, because this might probably be where I mistakenly understood (one of) them - the Bowditch starting data are quite self explanatory.

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