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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Captain Cook & celestial navigation
From: Robin Stuart
Date: 2020 Jan 30, 10:54 -0800
From: Robin Stuart
Date: 2020 Jan 30, 10:54 -0800
Geoffrey,
You asked: "Did I get that right?"
Your interpretation of what the article is telling you is correct but what it is saying is wrong. Cook measured the lunar distance and the altitudes of the Moon and the other body. These were "cleared" to obtain the geocentric lunar distance at the time of observation. Tables in the NA give lunar geocentric distances and not as is wrongly stated in the figure caption "...lunar distances for January 1769 as they would appear to an observer in Greenwich, England". Having obtained the Moon's geocentric lunar distance at the time of observation you use interpolation on the table to get GMT,
Robin Stuart