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Andres Ruiz wrote-

"The method described in Ocean Navigator is the one in Bowditch current 
edition."

Not quite. That article suggested observing 15 minutes before and after 
noon. Bowditch suggested a span of 30, either side. There's a big difference 
in the resulting precision.

There's no doubt the method can be got to work, as long as a sufficient span 
of time is chosen, which depends to a large extent on noon Sun altitude, and 
on the sea-state for observing. But the longer that time-span, the less 
appropriate it is to call it a "Noon sight". To preserve that catchy title, 
those who push this method, which is simply the old one of "equal 
altitudes", do their best to minimise the necessary length of that interval.

Andres' simulation would be interesting when applied to a latititude of say 
53�N, with a declination of -23�, when a low noon Sun makes things more 
difficult..

He added-
"Also I try this method aboard a sailboat and the results are acceptable due 
to the waves and roll and pitch"

That's intriguing. It would be interesting to see the numbers he came up 
with, in real-life; and what he considered acceptable.

contact George Huxtable at george@huxtable.u-net.com
or at +44 1865 820222 (from UK, 01865 820222)
or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK. 


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