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    Re: Prime Meridian on the move
    From: Bruce J. Pennino
    Date: 2016 Jan 15, 21:39 -0500
    Seems like everything is moving all the time. Continental drift,  internal molten mass, glaciers melting, mountains going up/down , giant rivers with moving banks, north magnetic pole moving , and all the other  stuff that would cause “brain ache”. Hard to believe “0” will ever be truly fixed (compared to what).
    When I made the obligatory trip  to Greenwich a few years ago I heard a great presentation..  Most interesting thing for me was the  following story....maybe true....maybe not...... To quote more or less from memory:  “ New observatory finished, telescope anchored in place, windows all done, chief astronomer does observations. He  found that a window was located improperly so that Zero longitude could not be sighted by a couple of inches, or something like that.  So 0 longitude was fudged by a small distance and the line was set”. Anyone else confirm this story for tourists?
    Happy  and Healthy New Year to all


    Sent: Friday, January 15, 2016 10:37 AM
    Subject: [NavList] Re: Prime Meridian on the move
    While I'm in tourist-exhibit-design mode:

    - show the ITRF velocity as well, so tourists can get a gut feel for tectonic motion
    - exaggerate the DoV by a factor of 100 in the optical plummet's field of view---problem solved


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