NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: instances of the use of "horizon grazing" technique
From: Greg Rudzinski
Date: 2009 Oct 6, 16:01 -0700
From: Greg Rudzinski
Date: 2009 Oct 6, 16:01 -0700
John, The technique that you are describing sounds like latitude by upper/ lower transit of a star. Stars are hard to see near the horizon which means that the transit should be more than 5� above the horizon. The altitude can be approximated by finger widths (rule of finger) of an outstretched hand. My finger widths are about 1�45' so that four fingers gives a 7� measure of arc. Haven't tried the finger rule for celestial purposes but have had luck in piloting applications such as doubling the angle on the bow and wether another sailboat is gaining or retreating by measuring the vertical angle of the mast head. Greg On Oct 6, 10:36�am, Apache Runnerwrote: > A number of emergency navigation sources talk about finding (very rough) > latitude by looking at the minimum altitude of horizon grazing stars. � �I'm > unaware of anyone that has actually used this technique, but perhaps someone > has used it in a real (as opposed to trial) situation. � Any anecdotes or > historical citations of this being used? > > John Huth --~--~---------~--~----~------------~-------~--~----~ NavList message boards: www.fer3.com/arc Or post by email to: NavList@fer3.com To , email NavList+@fer3.com -~----------~----~----~----~------~----~------~--~---