NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: NA daily pages, moon
From: Frank Reed
Date: 2008 Oct 30, 01:12 -0400
From: Frank Reed
Date: 2008 Oct 30, 01:12 -0400
Bill, you wrote: "The Nautical Almanac daily pages list the upper and lower meridian passage of the moon. Of what use is the lower-meridian-passage information in the latitudes that the majority of people live in and sail?" Completeness. Some people may want to use the NA in polar regions. And: "Perhaps a rough estimate of velocity and tides?" Yes, it's useful, just barely, for estimating tides if you already know some local data (the time offset between meridian passage and high tide is relatively stable in many areas). But I think there's general agreement that the data in that little moon box have very limited navigational value. For another example, why do we need to know the moon's percent illumination (to the nearest percent)? The percent illumination was added in the 1980s. Why wasn't the small phase diagram sufficient? -FER --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---