On the date of early Christian Basilicas (central Greece)

Abstract

The exact foundation date of many early Christian churches is still unknown or according to archaeologists' estimation it is attributed to a large time interval. According to a new astrogeodetic methodology, today it is feasible to assess it. This paper deals with the determination of the orientation, the foundation date and the dedication of nine Early Christian basilicas, situated in Central Greece. According to the suggested methodology, the appropriate geodetic and astrogeodetic measurements were carried out on the site of each Early Christian basilica in order to: Determine the accurate position on the surface of the earth by the calculation of its coordinates, Draw the accurate digital plan, Define the basic longitudinal axis, Calculate the astronomical azimuth of the basic axis via observations to Polaris (a Ursa Minoris), Create the profile of the perceptible horizon, Determine the apparent transit of the Sun for different dates. Combining all the above data for each Early Christian Basilica, the total geometric documentation of the monunent was made. The detection of its foundation date and its dedication were achieved with adequate precision and reliability. Last, their selectable and systematical astronomical orientations were registered and a data base including all the above data had been created.