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    Re: At the centre of time
    From: Douglas Denny
    Date: 2009 Oct 21, 02:25 -0700

    I should have continued with this quote too 
    from:- 
    http://gpsinformation.net/main/greenwich.htm
    --------
    
    "The Airy Transit's position
    
    Comparing the longitude of the Airy Transit in the system available in 1936 to 
    the longitude determined with space techniques gives a difference.
    
    Using Ordnance Survey Level 1 Transformation
    
      Airy Transit, GB36 =      N 51 28 38.265    E 00 00 00.418
      Airy Transit, ETRF89 =    N 51 28 40.1247   W 00 00 05.3101
    
      X 3980637.8044  Y - 102.4779  Z 4966897.8318
    
    The difference in longitude between the two systems at the Airy Transit is 
    102.478 metres. Therefore the International Reference Meridian is 102.5 
    metres east of the Airy Transit at Greenwich. As the IRM is tied to the 
    definition of time the real reference meridian to be used for the Millennium 
    is the IRM which, as shown above, is about 100 metres east of the Greenwich 
    Meridian." 
    
    --------------
    
    Douglas Denny.
    Chichester.  England.
    
    
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