L'astronomie égyptienne

Abstract

In Egypt, stars and planets were considered as gods and astronomy was practiced by priests in the temples. It was in an outburst of religious fervor that these priests-astronomers were observing the heavenly bodies, the motions of which perfectly measured the time of men. Thus, the order of the universe was a temporal one and they obser¬ ved the sun to fix the hours of the day and the stars to fix the schedule of the night ritual. The latter were preferentially zodiacal stars, the 36 decans. The first temporal cycle was that of the sun, which was Khepri, the sun appearing, in the morning, Râ, in the middle of the day, with all the power of its light and finally Atum, in the evening. A cycle similar to the fate of man. But the most important time cycle of Egyptian astronomy was that of the heliacal rising of Sirius, the goddess Hathor, the Lady of Denderah, with a yearly period of exactly 365,25 days, during all the history of Ancient Egypt. Thus, Egyptian astronomers built a calendar of 365 days, which was never corrected, and in which the heliac rising was evidently shifted at the rate of one day every four years. The year had twelve months of thirty days and a holy period of five days. Egyptian priests had set up this calendar to set the dates of the religious feasts and observed stars to fix the hours of the night. The orientation of the monuments, principally the pyramids, was also a task of Egyptian astronomy. In the Ptolemaic epoch, the temple of Denderah was adorned by the great famous zodiac, presently in the Louvre Museum in Paris. It worked as an universal julian calendar, as well as for astrological ends.