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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: The Running Fix on an Ellipsoid
From: Andrés Ruiz
Date: 2017 Feb 7, 10:42 +0100
From: Andrés Ruiz
Date: 2017 Feb 7, 10:42 +0100
You wrote:
Dear Robin do not put your eye focused at the ellipsoid.
“We cannot carry on putting the cart before the horse” or ”build the house from the roof”
The key point is in the definition of the CoP.
Circle of equal altitude: a circumference on the surface of the earth, on every point of which the altitude of a given celestial body is the same at given instant.
As I said before, it not depends on the Earth´s model: sphere, ellipsoid or geoid.
The center of the CoP is the geographical position of the star.
The distance from this center to the CoP is the zenith distance of the celestial body.
Distance: great circle, great ellipsoid, geodesic, ..., the real one.
Regards,
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