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    Re: Unexpected USNO height correction precepts
    From: Mehmet Guzey
    Date: 2018 Dec 18, 12:03 -0800

    Hello Antoine,

    I need to apply to your expertise regarding your below post:



    I am actually computing λ in the plan containing Sun Center - Planet Center - Earth Center since λ then entirely shows up as a unique correction to the angular variable measured in this specific plan.

    Due to the very special configuration of both Venus and the Sun being in almost the very same Azimuth in this example, λ also shows up here as a simple and unique heigh correction (no Azimuth 

    correction) from Venus center towards the Sun Center which is higher. Accordingly the center of Venus light is exactly above the center of Venus by a quantity equal to 0.31' as earlier computed.


    For some time, i have been trying to follow your posts on venus phase correction calculation and USNO height comparison.

    it was very informative and i was able to calculate the same phase correction value (λ=0.31') thanks to your findings.

    However, i guess i am missing an important component (Azimuth correction) to make sure that i can consistently obtain the right values for phase correction, not only for that specific extreme case (almost the same sun-venus azimuths and sun is heigher than venus) but also for other cases as well.

    Could you please help me on howto find the azimuth correction to be applied to venus phase correction value and what other steps, if any, to follow for general venus phase correction procedure?

    Thank you very much in advance...

    Best Regards...


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