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    Missed opportunities, was: Moon eclipse
    From: Alexandre Eremenko
    Date: 2004 Oct 30, 14:25 -0500

    According to our experiments with this moon eclipse,
    the records of similar observations in XIX century,
    and Frank Reed's assessment of precision
    of astrolabes,
    
    "Assuming roughly two minutes error in eclipse event
    timings and two minutes error in local time,
    the average expected error
    would be
    about three minutes --less than a degree error in longitude."
    
    and
    
    "the world could have been
    mapped in longitude with good accuracy thousands of years ago."
    
    This is enormously more precise than
    you can hope to measure by "dead reckoning" in a land travel.
    (Speaking, for example of the longitude distances like
    Paris-Moscow or from Rome-Beijin).
    
    Given that the Lunar method was proposed by Hipparchus
    in III cent BC, it is surprising that it was so rarely used
    in the following 2000 years, as Herbert Prinz,
    apparently wery knowlegeable in the history of this question,
    testifies.
    
    But I agree that speculation on "why was this so" is out
    of the scope of this list. (On my opinion, this is related
    to the hudge decline in the general attitude to science
    in the almost 2000 period betweeh Hipparchus and XVIII century.)
    
    Alex.
    
    
    

       
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