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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Swinging the Arc
From: Alexandre Eremenko
Date: 2004 Dec 5, 16:40 -0500
From: Alexandre Eremenko
Date: 2004 Dec 5, 16:40 -0500
On Sun, 5 Dec 2004, Frank Reed wrote: > 3) Swinging the "right" way by rotating about the line of sight > to the Sun. > Sun's image remains essentially centered in the field of view. How can you possibly do this in practice?? Except by invereting your sextant and looking at the Sun through the horizon mirror? I mean when you look through the telescope how can you feel the correct direction to the Sun to swing about it? Maskelyne also asks the same question and concludes that one has to rotate the sextant about BOTH horizontal and vertical axes. When the altitude is small it is enough to rotate about horizontal axis, when it is large, the main part of the motion is about the vertical axis. Alex.
