NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David Fleming
Date: 2011 Aug 12, 17:54 -0700
I now conclude that neither time nor position can be extracted from the three lunar distance data given.
On the celestial sphere the three star positions are fixed.
The actual moons position on that sphere moves by .6 degrees in the hour from 0300 to 0400.
The lunar distances however are apparent measurements due to parallax moving the apparent moon on the cellestial sphere. The apparent position is in a circle about the moons actual position given by the almanac data. That parallax could be as +/-1 degrees.
Thus whatever time during the hour a measurement was made is possible to find an observational position that would the apparent position to any other possible of the actual moon. The parallax has wiped out the time information.
Not knowing the time we do not know the actual position of the moon and therfore have no knowledge of the parallax.
Dave Fleming
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