A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Robin Stuart
Date: 2015 Feb 26, 04:55 -0800
While we're on the subject, in your book "Celestial Navigation in the GPS age" you give an elegant solution to the double altitude problem using 5 successive applications of the cosine rule of spherical trigonometry. What is the origin of this method?