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    Re: Basics of computing sunrise/sunset
    From: Andrés Ruiz
    Date: 2009 Jun 18, 12:15 +0200

    Yes, it is easier:


    0 < t < 24 h



    t [hours]

    GHA0 = GHA at 00:00 UT of the current day

    GHA1 = GHA at 00:00 UT of the current day+1



    -----Mensaje original-----
    De: NavList@fer3.com [mailto:NavList@fer3.com] En nombre de Bill
    Enviado el: jueves, 18 de junio de 2009 11:32
    Para: NavList@fer3.com
    Asunto: [NavList 8686] Re: Basics of computing sunrise/sunset




    Combine the computed LHA with the longitude in the usual manner, and you

    have your Greenwich Hour Angle (GHA).


    Take the computed GHA and find the value just below it on the daily page for

    your date.  Subtract that tabular hour's  GHA value from your computed GHA

    and convert the difference from arc to time.  That time conversion plus the

    UT/GMT for the hour used is the UT of your sunset or sunrise.


    The above allows you to escape messy Equation of Time adjustments and

    interpolations for your local time.


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