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Robin,
Are there published  suggestions related to the distance between
assumed position and GP of the celestial body?  Obviously if you are
close enough for the GP to be on your plotting sheet you can draw a
circle of position.
Bill

On Mon, 18 Mar 2019 at 00:33, Robin Stuart  wrote:
>
> Geoffrey,
>
>         The authors of the Nautical Almanac believe this to be 20 nautical 
miles. The method they describe in the section Position from intercept and 
azimuth by calculation on p.282 (2010) requires that the procedure be 
iterated until the initial and final estimates of position are within 20 
miles of each other.
>
> “If d exceeds about 20 nautical miles set LF = LI, BF = BI and repeat until 
d, the distance between the position at the previous estimate and the 
improved estimate, is less that 20 nautical miles”
>
> The equations being used in the least squares calculation of position are 
exact in within the straight LoP approximation. The iteration is required to 
ensure that the approximation is a good one and that curvature of the LoP’s 
can be neglected,
>
> Robin Stuart
>
> 

   

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