B. Frischer / C. Johanson / C. Stanish / D. Dearborn
(Institute for Advanced Technology in the Humanities, University, Charlottesville, Virginia, USA)

The purpose of this paper is to present a “virtual-empirical” test of the Dearborn-Bauer thesis about the possible alignment of two Inca towers at the north end of the sanctuary of the Sun on the Island of the Sun in Lake Titicaca (Bolivia). According to the thesis, the towers in questions were not (as has sometimes been thought) tombs but markers of the position of the sun at sunset on the winter solstice. An actual empirical test of the thesis could not be undertaken because of the well-understood change in the Sun’s apparent circuit through the sky during the past 500 years since the Temple of the Sun was constructed. To conduct the “virtual-empirical” test, a 3D computer model of the topography of the island and the sanctuary was built. Azimuthal data supplied by NASA’s Jet Propulsion Laboratory made it possible to reconstruct the apparent course of the Sun through the sky at sunset on the winter solstice in the year 1500 CE, the approximate date of construction of the sanctuary. In the presentation in Vienna, the results of the virtual test will be presented and the validity of the Dearborn-Bauer thesis will be gauged. keywords: solar alignments, Inca, solstice