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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: An exotic lunar distance puzzle
From: Marcel Tschudin
Date: 2011 May 5, 18:24 +0300
From: Marcel Tschudin
Date: 2011 May 5, 18:24 +0300
Greg,
Unfortunately I coudn't follow your thoughts from your diagram. Yesterday I wrote: "I hope to find some time later today to explain that there is a corrective contribution to be added to the geometrical dip." Well, yesterday it became too late.
In the attached figure the arrow from the space shuttle to the horizon represents a first estimation of the geometrical dip.
The refracted ray (red line) grazes the horizon at some distance further away.
From this tangent point the geometrical direction of the space shuttle corresponds to the second arrow which increases at the space shuttle the first estimation of the dip. This new geometrical dip results now also in a slightly different refraction which has again to be deducted from it.
The matching (correct) dip would likely have to be found by repeating this procedure, thus iteratively.
Marcel
Unfortunately I coudn't follow your thoughts from your diagram. Yesterday I wrote: "I hope to find some time later today to explain that there is a corrective contribution to be added to the geometrical dip." Well, yesterday it became too late.
In the attached figure the arrow from the space shuttle to the horizon represents a first estimation of the geometrical dip.
The refracted ray (red line) grazes the horizon at some distance further away.
From this tangent point the geometrical direction of the space shuttle corresponds to the second arrow which increases at the space shuttle the first estimation of the dip. This new geometrical dip results now also in a slightly different refraction which has again to be deducted from it.
The matching (correct) dip would likely have to be found by repeating this procedure, thus iteratively.
Marcel