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    Re: Daylight Venus Lunar
    From: Antoine Couëtte
    Date: 2023 May 27, 11:26 -0700

    From only the 3 published angles : 36°50', 62°41' and 63°02', it is possible to obtain 3 other angles :

    UT = 21h42m28 s   Lat = N41°28' and Lon W 071°11' (using Venus Center, with own Ephemeris slightly "off" by 0.04') 

    from which, comparing with Beavertail Point position (N41°27'  W071°24') we can observe an error in longitude equal to 13' , quite close from the published value (12').

    Given the harsh environment, this Daylight Venus Lunar is nothing short of a remarkable achievement.

    I would surmise that the Venus Center of light was actually observed, and it differs from the Center of Gravity by 0.07', which translates into a slightly different determination : UT = 21h42m19s / N41°28' / W071°09' which yields a slightly increased Longitude error equal to 15' this time, which - again and given the environment - does constitute a good and solid result.

    Thanks to you Frank for this very interesting and didactic example.

    Antoine M. "Kermit" Couëtte

       
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