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    Re: Direct methods
    From: Dave Walden
    Date: 2007 Nov 1, 15:49 -0700
    Attachments seem it or miss.  Here's a second try

    d walden wrote:
    It is of course possible, as has been pointed out, to calculate the latitude and longitude of the points of intersection of two circles of position directly with neither an estimated nor an assumed position.  Nor in fact are altitudes and intercepts or any plotting needed.  The intersection of cones method, described by Frank in the discussion of latitude by lunars, and shown in a previously posted FORTRAN and Maxima example can be used.  A few minor changes to the programs posted are needed.
     
    The problem is, in fact, slightly easier.  It can be done with intersecting planes.  The attached little spread sheet is an example of how.  One enters with the altitude, declination, and GHA of two bodies.  Out come the latitudes and longitudes of the two intersection points.  If you have three bodies, pick a different pair, and two of the points should wind up quite close.  There you are.
     
    Seems to be working for me, but no guarantees.
     

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    File: 103728.vanallenfix_4.xls
       
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