NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Lunar longitudes, not by lunar distance.
From: Geoffrey Kolbe
Date: 2009 Aug 09, 16:46 +0100
From: Geoffrey Kolbe
Date: 2009 Aug 09, 16:46 +0100
George [NavList 9432] wrote >Indeed, that would be the case, if we were measuring azimuths, but we're >simply timing the Moon as it passes a vertical line, so the correction is >constant in time, independent of altitude. Sorry George, am I missing something here? The point I was alluding to is that when you time the edge of the moon as it touches the vertical hairline, the centre of the moon is then not just a 'semi-diameter' away, but a 'semi-diameter divided by the cosine of the altitude' away in azimuth. Since the tables for the moon's position are for the centre of the moon, that is the correction you must make to determine the LHA between the moon and the star at that moment in time. Is that not so? Geoffrey --~--~---------~--~----~------------~-------~--~----~ NavList message boards: www.fer3.com/arc Or post by email to: NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
