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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Emergency sun declination
From: Jim Thompson
Date: 2004 May 19, 18:37 -0300
From: Jim Thompson
Date: 2004 May 19, 18:37 -0300
What about this method for emergency calcuation of declination? 1. Label a compass rose June 22 at 000o, Sept 23 at 090o, Dec 22 at 180o and March 21 at 270o. 2. The radius on the vertical axis is the declination of the sun. A horizontal line from any date around the circle intersects that vertical radius. 3. Measure the length of the vertical axis from the center to the intersection of the horizontal line, divide that length by the full radius, and multiply that ratio by 22.5o. 4. Error is +/- 0.5o. Jim Thompson jim2@jimthompson.net www.jimthompson.net Outgoing mail scanned by Norton Antivirus -----------------------------------------
