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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Position from crossing two circles : was [NAV-L] Reality check
From: Frank Reed CT
Date: 2006 Jun 15, 01:56 EDT
From: Frank Reed CT
Date: 2006 Jun 15, 01:56 EDT
"I moved a penny across a celestial globe to visualize Zevering's procedure and forgot for a moment that this was exactly what I had argued against earlier!" So I'm up in the high Arctic in the winter driving across the ice. I get out my bubble sextant and through broken clouds I get an altitude of Polaris at 87 degrees. I see Jupiter through a break in the clouds a minute later low in the sky but I don't have time for an altitude. Now I travel for sixty miles in a straight line 30 degrees to the left of the azimuth of Jupiter at the time of the first sight (it's not possible for me to say "I traveled 'north' for sixty miles" since I can't measure that, right?). The clouds break, and I then shoot an altitude of Jupiter and find it's [pick a number] degrees high. I want to advance my initial circle of position for Polaris and cross it with the position line for Jupiter. How do I do that? Is my advanced circle of position distorted? -FER 42.0N 87.7W, or 41.4N 72.1W. www.HistoricalAtlas.com/lunars
