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Coordinates
From: Aubrey O´Callaghan
Date: 2001 Sep 25, 8:09 PM
From: Aubrey O´Callaghan
Date: 2001 Sep 25, 8:09 PM
As an engineer I have come across an interesting set of coordinates. In Venezuela these is a coordinate system called La Canoa. Apparently it is referenced to a cathederal in the city of Maracaibo. La Canoa is based on an inverse flattening of 1/297 (WGS84 is 1/298.257223) with semi major axes of 6378388 and 6378137 respectively. I have in front of me 2 sets of coordinates one based in "La Canoa coordinates", the other in WGS84. I am surprised to find a difference in the longitude. Does anybody have an explanation for the longitude change ? WGS84: 10 deg 14 min 00.77sec N 71 deg 28 min 23.70 sec W La Canoa: 10 deg 14 min 12.28 sec N 71 deg 28 min 16.52 sec W It should be noted that the information I have for the La Canoa gives the spheroid as International and datum as La Canoa, I think that this is the Hayford International spheroid. The WGS 84 gives the spheroid as WGS84 and the datum as WGS 84. As I said earlier the longitude change has me intrigued, but I can find no reason for the change in Admiralty Navigation books (I have not a copy of Bowditch). Aubrey.
