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    Re: LOP's without DR Position
    From: Antoine Couëtte
    Date: 2015 Feb 25, 07:54 -0800

    Thank you Yves for your kind and nice comments. We are all onboard the same vessel as I can see!

    RE: your own paragraph numbering:

    1 - Happy to see that MPS can accomodate as many bodies as needed. This is what I thought, but I was no longer sure. Therefore, we can definitely now list MPS as a strong player in 4G.1, and the only one published performer so far in this 4G.1 category.

    3 - As Gauss's method is limited to equal altitude observations, then it probably falls closer to the "genuine" "Douves's Problem so clearly defined by Frank lately (RE: introduction lines of http://fer3.com/arc/m2.aspx/LOPs-without-DR-Position-Cou%C3%ABtte-feb-2015-g30440

    5 - Yes please, be so kind as to send me a copy of  General Hourneau's paper. This way, I am also sure to recover my own sleeping copy too ...

    What definitely rang a bell during my internet research yesterday was picking up the word "canonical" (from: "canonical equations") off the internet abstract (http://cat.inist.fr/?aModele=afficheN&cpsidt=19474690). That is M. Hourneau indeed I had been presuming during this exploration! One correction of importance though ... General and not Colonel: my most sincere apologies to you General! (if you are reading me).

    7 - Yes, I totally agree: considering the Earth as a Sphere rather than an Ellipsoid introduces for the Moon a systematic error on its computed parallax reaching 10" of arc under extreme cases: Moon closest to the Earth and very low apparent altitudes observed from high latitudes (and maybe also extreme Moon Declination, but I do not remember for sure whether the Moon Declination is a relevant variable here). Whatever ... for apparent altitudes below about 10° and to a precision better than 0.1' the Moon Parallax correction does remain Observer's Latitude dependent.


    Again, what really puzzles me is that method 3G.1 is so straightforward, so immediate (if not "so easy") that I would be very surprised if it had definitely not been published somewhere else before 1976.

    But we all know of a celebrated similar case quite amazing too. Marcq Saint Hilaire's method is also very simple, if not "so simple" and so much easier than most of - if not all - other methods in use at its time and it is so powerful too! And it nonetheless was published in 1875 only.

    However it might not be a sufficient reason to claim: Let's then wait for a CelNav tremendously simple and amazing discovery by Year 2077!

    Well .. I am to conclude here exactly like I concluded yesterday:

    I am still interested in knowing wether somebody published (when and where ?) a solution matching the "Geometrical 3D/3 Plan Method" before it was published in France in 1976.

    Thanks again to you Yves


    Antoine M. "Kermit" Couëtte

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