NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Robin Stuart
Date: 2013 Sep 21, 12:30 -0700
Re: https://NavList.net/m2.aspx/LADEE-Moon-Probe-Puzzle-Bernecky-sep-2013-g25134
Bob,
Your analysis indicated that accounting for the ellipsoidal figure of the Earth had quite a large effect on the estimation of the position of the location where the photograph was taken. Looking into it a bit further I suspect that your approach of adjusting the Earth's radius for latitude does not capture the full suite of effects such as the fact that the vertical does not pass through centre of the Earth. Conversion between latitude, longitude, altitude and rectangular coordinates is described at
https://www.navipedia.net/index.php/Ellipsoidal_and_Cartesian_Coordinates_Conversion
For example your calculation for the position of the rocket gives p = ( 0.2681, -0.7625, 0.6229 ) whereas using the methods from the link produces p = ( 0.2685, -0.7635, 0.6196 ). Full incorporation of the effect of the figure of the Earth requires only some relatively minor tweaks to your original calculation which I have outlined in the attached summary. I have included these in an updated version of my calculation along with the adjustment from 2000 to 2013 coordinates but the new results remain stubbornly close to my original one,
Regards,
Robin Stuart
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