# NavList:

## A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

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Re: Figure out LAN?
From: Samuel L
Date: 2014 Oct 2, 04:28 -0700

Paul,

I was basing my method of determining LAN from this post; (The topic is "lat/long from meridian passage"

http://fer3.com/arc/m2.aspx/latlong-from-meridian-passage-LaPook-jan-2011-g15450

....and Gary's method-

Another way to calculate the time of local noon is to find the time when the GHA of the sun equals you longitude, in this case 76° 21.7' west. At 1700 Z the sun's GHA was 72° 36.8' which subtracted from the longitude leaves a difference of 4° 14.9'. We then look in the increments table in the NA to find out how long it takes for the sun's GHA to change by this amount and we find that it is between 16 minutes and 59 seconds and 17 minutes. We then add this extra time to 1700 Z to find the time on the meridian of 17:16:59.5, not surprisingly, the same result as when doing the computation using the equation of time.

gl

-------------------------------------------------

Sam

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