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Jeff Morris
 
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Default The noon sight - it's a beautiful thing.

Its the funny "figure 8" on the globe - it describes the "equation of time"

http://hpccsun.unl.edu/nebraska/analema.html

world's largest analema:
http://www.uwm.edu/~kahl/Images/Weat.../analemma.html

the equation of time:
http://www.astronomynotes.com/nakedeye/s9.htm

one page table that should be enough for Longitude:
http://home.netcom.com/~abraxas2/eot.htm



"otnmbrd" wrote in message
ink.net...
BG You'd need to define, as I haven't a clue as to what that is
(Analema).
When you get "into" the study of methods of navigation, you tend to find
many ways and "publications" that have been or are used for sights.
Personally, I still prefer (or did when I was using them) the older
tables (214?) for sight reduction.

otn

Jeff Morris wrote:
For Longitude can't you just use an Analema? (This post was really an

excuse to
use that word!)

Actually, a one page text version of the Analema will be accurate to about

10
seconds for any year. The declination of the Sun at meridian passage,

needed
for Latitude, can also be found in a "one page perpetual" version, accurate

to
about 12 arc-minutes with interpolation.

If anyone is interested in emergency traditional navigation, they should

find
"Particularized Navigation, How to Prevent Navigational Emergencies" by

Francis
W. Wright; its out of print but available from some sources. This includes

a
small book on celestial, and even smaller pamphlet with tables, and even yet
smaller sheets for lifeboat navigation.