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    Re: Noon sight for longitude
    From: Andrés Ruiz
    Date: 2008 Jul 14, 08:20 +0200

    The derivation of the equations in "POSITION FROM OBSERVATION OF A SINGLE BODY 
    James N. Wilson Vol. 32, No. 1, 1985" is totally general, and under the 
    conditions George says, they must work.
    For the simulation in [NavList 5794], I have used the simplified formula:
     Sn = V * DCOS(R)
     d = dDecdt
     TimeOfLANcorrection = 48# / PI * (Sn - d) * (DTAN(B) - DTAN(Dec))
    But for this simulation I have used the general one, because a component of 
    the course in the N-S and E-W axis appears:
     V = V / 60#
     Sns = V * DCOS(R)
     Sew = V * DSIN(R)
     dBdt = Sns
     dLdt = Sew / DCOS(B)
     dLHAdt = dGHAdt + dLdt
    TimeOfLANcorrection2 = 3600# * 180# / PI * (dBdt - dDecdt) * (DTAN(B) - DTAN(Dec)) / (dLHAdt * dLHAdt)
    The solution is t LAN: 15:36:51 from data and form James equation!!!
    -----Mensaje original-----
    De: NavList@fer3.com [mailto:NavList@fer3.com] En nombre de George Huxtable
    Enviado el: viernes, 11 de julio de 2008 17:32
    Para: NavList@fer3.com
    Asunto: [NavList 5798] Re: Noon sight for longitude
    Andres Ruiz wrote-
    Andres' simulation would be interesting when applied to a latititude of say 
    53ºN, with a declination of -23º, when a low noon Sun makes things more 
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    File: 105836.t-lan.zip
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