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Historical geodesy

December 16 2009 | 0 comments
Categories: Map Data

I've got a question about historical geodesy. I have a historian colleague who wants to map the journeys of whaling ships from entries in the ships' journals. The ships sailed from the Atlantic and throughout the Pacific in the 1600-1700's. Now I'm sure they weren't using WGS 84 at the time. Does he need to worry at all about what geodetic system to use in his GIS? I realize longitude was a problem then anyway and nothing was probably very accurate, but it's a good question that I will probably need to get answered again in the future.

Mapping Center Answer:

That would have been before and while they were performing "arc measurements" in the 1700s. See http://en.wikipedia.org/wiki/History_of_geodesy. Probably the easiest thing to do would be to use a sphere as "close enough."

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