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It's good to see that Frank is going to have another go at this interesting
topic that we considered in the thread "Latitude from lunar distance", back
in 2006.
I am sorry not to be attending.

Given the chance, I would certainly try to get an example calculation from
him, even with fictitious numbers; and ask how a navigator at sea, without
internet access, would obtain sufficiently accurate predictions of the
Moon's position, other than by using the Nautical Almanac. Also to ask for a
complete error-budget, to include numerical estimates of the the following
errors and how they combine-
Systematic errors such as; sextant calibration, sextant adjustment, index
check, observer irradiation correction and/or personal bias, celestial
position prediction, any abnormal atmospheric refraction.
Random errors (and therefore reducible by averaging many observations):
Observer's scatter between readings.

These were all questions asked of Frank on that earlier thread, some by me,
some by others. All were evaded.

It would also be useful to be clear whether any accuracy claims that are
made will be in terms of maximum expected error,  standard deviation
(one-sigma), or some other multiple of sigma.

Perhaps Frank will respond, at the Mystic meeting, and will report back.

George.

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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