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    Prime Meridian on the move
    From: Peter Monta
    Date: 2016 Jan 15, 07:06 -0800
    GPS World has a brief discussion of the Greenwich Meridian by the authors of the recent paper on its history and relationship to the ITRF:

    http://gpsworld.com/prime-meridian-on-the-move/

    Incidentally, does anyone know the status of any effort to make a small auxiliary tourist exhibit at the ITRF meridian?  They really should.  I was at Greenwich about five years ago, and did the obligatory 100-meter walk east, but there was nothing but grass and an asphalt footpath.

    Required:

    - brass survey disk (with suitable monument) at the ITRF meridian with explanatory plaque
    - small fixed telescope pointing downward, looking toward an illuminated target at ground level.  "This way to center of Earth."  The DoV might be too small to show clearly, though.
    - careful survey of the tourist line and the new monument, good to a centimeter or so.  This would take only a couple of hours with a survey-grade GNSS receiver and a total station.  No need to set up on the tourist line itself---it can all be done with a few setups on the open areas nearby with intervisibility to the tourist line and the new monument.

    Cheers,
    Peter

       
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