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    Re: Dropping leap seconds and the impact on celestial navigation
    From: Fred Hebard
    Date: 2011 Sep 12, 12:36 -0400

    I'm afraid I was speaking rather imprecisely, referring to noon as the 
    meridian and 11:30 am as the time of day on a mechanical watch.
    
    On Sep 12, 2011, at 12:30 PM, Herbert Prinz wrote:
    
    > On 2011-09-12 14:18, Fred Hebard wrote:
    >> I was merely expressing concern at decoupling of days from the course of the sun.  No tongue in cheek.
    >> 
    >> 
    >>> On 2011-09-10 16:24, Fred Hebard wrote:
    >>>> ... I wonder what will happen 200 years from now.  Will noon be 11:30 am? 
     That would be unacceptable to me.
    > 
    > 
    > Fred,
    > 
    > Let me double check that I understand the terms correctly as you mean them 
    in your question "Will noon be 11:30 am?"
    > 
    > If the question is to be taken at face value, "meridies" then stands for the 
    original meaning "middle of the day", as we reckon it, i.e. 12:00, regardless 
    of what it means astronomically, (hence a.m. is any time between 00:00 and 
    12:00); While "noon" stands for the moment that the sun (in some sense) is 
    passing over some meridian?
    > 
    > These definitions are reasonable, but they no longer go without saying. My 
    uncertainty is just one example how difficult the precise discussion of this 
    topic is, given that the terminology is so fraught with history and 
    connotations and so widely used in other fields than astronomy (geography, 
    horology) and everyday speech.
    > 
    > Herbert Prinz
    > 
    > 
    > 
    
    
    
    
    

       
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