Astronomical Alignment of the Osireion with Sirius
heliacal rising of Sirius preceding the Nile flood and witnessed by an ivory tablet found near Abydos by Petrie in 1902. The tablet, whose meaning despite being questioned by Clagett [Clagett96], seems to effectively refer to the star Sirius calling it the "herald of the new year and flood". Finally, the presence demonstrated by Jim Westerman of a water source coming directly from the Nile at the Abydos site suggests a thematic affinity between the fundamental first nucleus of the Osireion and the mysteries of rebirth to which the star Sirius was associated. Having established that the most plausible astronomical phenomenon to which the construction of the Osireion can be correlated is the heliacal rising of the star Sirius associated with the Nile flood period, we notice that effectively in 3500 BC Sirius on the day when it rose heliacally announcing the flood rose with $33°$ inclination relative to geographic East, perfectly aligned with what now constitutes the entrance corridor to the Osireion. Although there is thus an agreement between the orientation of the Osireion and the star Sirius around 3500 BC, however we consider the structural and astronomical coincidence not sufficiently demonstrated. It is necessary to specify that the current entrance corridor of the Osireion is certainly later than the construction of the first nucleus of the site and although effectively placing the sarcophagus chamber along the direction orthogonal to the entrance corridor is a typical theme of the Old Kingdom, however the angulation of the corridor would necessarily date an Osireion with planimetric conformation very similar to the current one already in 3500 BC (being the star Sirius in 3000 BC already sensibly out of angulation or about $30°$). This results incompatible with currently known Egyptian architectural history as there are no similar architectural elements except with the construction of the pyramids of the Old Kingdom in the IV dynasty.