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Re: Advancing a position circle. was : [NAV-L] Positionfromcrossing two circles
From: Andrés Ruiz
Date: 2015 Feb 23, 12:47 +0100
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From: Andrés Ruiz
Date: 2015 Feb 23, 12:47 +0100
Dear Robin,
Well done!
This remind me our private conversation about this issue in 2011:
...
- The correction V*(t-tfix)*COS(Z-R) for Ho is only an approximation. See: Running fix- Papers.zip, I have implemented this methods.
An exact solution says that the transferred CoP is deformed:
- the radius ZD is the same in the original CoP and in the transferred one.
- But its center (Dec, GHA) depends on your position. If You plot the circle, you obtain different centers choosing different points of the circle(lat,lon).
- Thus, only one of the solutions for a double altitudes problem is OK, mathematically.
See:
...
Also I discussed about this with GH and H. Zevering in 2010. The problem was that without a plot like the ones you provide us, is very difficult to illustrate this fact.
Thanks and best regards!
