A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Brad Morris
Date: 2016 Jan 3, 11:25 -0500
Glad to see you!
There has been some discussion of performing the lunar distance computation with a slide rule. What is your estimate of the number of significant digits for the lunar distance computation?
This kind of calculation requires few significant digits, and thus can be done with a slide rule. You can also time how much it takes by hand with pencil, as it was done in the old times, without a calculator and without a slide rule. However the main calculation which we do in CelNav, solving a spherical triangle, requires 5-6 digits, and this is not possible with a slide rule. Perhaps for this reason a slide rule is not in the list of standard equipment for a celestial navigator.