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    Re: Latitude by Lunar Distance
    From: George Huxtable
    Date: 2006 Nov 11, 16:25 -0000

    Frank Reed wrote-
    
         ...did YOU ever realize that you could determine a  true
    | position fix using lunar distances without any horizon at all? I
    think it's
    | quite a novel concept for this group of people.
    
    Yes, I agree, it was an interesting notion, well worth bringing to our
    attention. A notion which is NOT devalued by the fact that it was
    first thought of nearly a century before; a fact which was also worth
    bringing to our attention. Whether that notion was practical or
    useful, then or now, is another matter. It was somewhat tarnished by
    Frank's rather extravagant claims made about its precision "to six
    miles".
    
    But Frank is being over-sensitive when he writes-
    
    I suppose that's why a couple of
    | people were determined to attack it instead of trying it out.
    
    I recognise myself as one of those couple, and wonder what Frank
    expects to get when he presents such a notion to our list. What he
    will get will be scrutiny, if this list is doing its job. Any such
    proposal will be unpicked and examined for holes and flaws. If it
    passes that test without serious defects coming to light, it's an
    indication (but nothing more than that) that perhaps the idea is
    indeed valid. This list acts an an almost-instant peer review, for
    which I have been truly grateful when it has found flaws in my own
    arguments; a more frequent occurrence than I wish to recall. We are
    not a mutual admiration society, and thank goodness for that.
    
    Finally, Frank has been asked to explain a procedure for deducing
    observer's position from two Moon-star distances, quoting numbers.
    Even a contrived, fictitious example would be worthwhile. That would
    allow us to understand where his predicted celestial positions are to
    come from (for example), how resulting position-lines are to be
    plotted, how an overall error-budget can be estimated, and whether his
    estimate of a result to six miles is at all reasonable. Is it
    necessary to presume an approximate observer's position beforehand? I
    still look forward to seeing how the job is to be done.
    
    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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