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    Re: Sun Moon Lunars to 155 degrees
    From: Antoine Couëtte
    Date: 2010 Mar 31, 23:09 -0700

    Dear Dave,

    Thank you very much for your very precious insights on OHAMANENO HARBOUR. Now we have full consensus on the coordinates of the Vessel Anchoring site, to certainly better than 1 mile.

    We can immediately notice that from such position, well over 50% of the horizon is in the direction of nearby land which restrict the horizon.

    From this now certain position, I will compute all FOUR Lunars backwards, in order to best obtain their UT's.

    And for each of these Lunar UT Times (unfortunately, no better or "less bad" assumption here), I will both :

    - compute the Bodies Azimuts and then check whether the horizon was obscured or not (i.e. restricted waters due to nearby land) in their directions, and also

    - compute UL/LL heights for various HoE's (O', 12' and 24') and directly compare these to the published heights.

    We probably should assume that only the Heights taken over non-restricted waters, i.e. within the Azimut range [175°-312°] and [326°-338°], could be then accurately measured. I doubt that they would have bothered to "fine-tunely" correct their restricted water heights (if any) for "dip short of the horizon".

    Hopefully I have time to compute and publish everything before I return flying.


    Anyway, I just indicated here-above the guiding lines of recommended next computations in order to best determine the "essence" of the published heights, and in particular whether thay have been corrected for DIP or not ... We already have independent crosschecking from Dave that HoE {at} 12' might not seem far from the truth ...


    Meanwhile, if somebody ( Andres, Other(s) , ... ) wishes to perform these calculations on his own and publish his results as soon as he is ready, no worries at all ! Since it is always very instructive to cross check one another's results, I would say here : "The more, the merrier" !


    Thank you also to you Jim Wilson, and to Brad and George for their most recent contributions.


    Best Regards to you all


    Antoine M. "Kermit" Couëtte


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