This is an interesting paper on the topic: Determination of the CNGS Global Geodesy [1]. It discusses how the distance traveled by the neutrino beam was calcul

This is an interesting paper on the topic: Determination of the CNGS Global Geodesy [1]. It discusses how the distance traveled by the neutrino beam was calculated. It covers GPS measurements, tidal effect considerations, the Sagnac effect [2], etc. [1] PDF: http://operaweb.lngs.infn.it/Opera/publicnotes/note132.pdf http://operaweb.lngs.infn.it/Opera/publicnotes/note132.pdf [2] http://en.wikipedia.org/wiki/Sagnac_effect http://en.wikipedia.org/wiki/Sagnac_effect