NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: NA daily pages, moon
From: Bill B
Date: 2008 Oct 31, 01:27 -0400
From: Bill B
Date: 2008 Oct 31, 01:27 -0400
Thanks Frank > 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? Slipping into astronomy, at what time/longitude is the exact percentage quoted? When I see it at 86d W can it be the same percentage as the time/longitude used for the percentage? (I've never quite figured out all the moods of the moon.) On the warm-fuzzy side it changes so much day-to-day it is just comforting to know vs. the diagram. Percentage coupled with rise/set/or meridian passage is also a nice way to determine the day in a lifeboat situation if I recall. On a more practical side for lunars mavens, I like to look at the raw sun vs. moon meridian passage times to determine when the relationships are within range. A sliver may be theoretically visible during daylight, but below a certain percentage I am totally unable to see it with the naked eye, as well with the sextant scope. Bill B. --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---