NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: How Many Chronometers?
From: Geoffrey Kolbe
Date: 2009 May 07, 12:40 +0100
From: Geoffrey Kolbe
Date: 2009 May 07, 12:40 +0100
List member John Karl, in his book "Celestial Navigation in the GPS
Age", has a nice little section on page 73 entitled Time from a
Lunar LOP and a Star Fix. The essence of the method is the LOPs from
a number of star fixes will cross neatly at a given point on the chart,
but that point will in error in longitude due to the error in the
chronometer. The longitude error in a lunar LOP will be slightly
different due to the faster motion of the moon across the sky. The trick
then is to adjust the time so that all LOPs - including the lunar LOP -
cross at the same point. The amount of adjustment required gives the
error in the chronometer.
I had not seen this described before and thought it quite neat.
Geoffrey Kolbe
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I had not seen this described before and thought it quite neat.
Geoffrey Kolbe
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To post, email NavList@fer3.com
To , email NavList-@fer3.com
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