On the structural plane, the temple of Isis is nothing else but a small-sized reproduction of the vast temple dedicated to the Hathor goddess. This temple was erected under the reign of Ramses II, that is to say, during the first part of the XIIIth century before our era. Its rebuilding began on the 16th July 54 before our era. The famous round zodiac long ago decorated the ceiling of the osirean chapel. It is a map of the sky, circular in shape, which twelve figures support : four goddesses personnifying each a cardinal point - the pillars of the sky in a way ; and eight kneeling gods - falcon-headed gods symbolizing eternity in this case.

Localization of the different areas of the sky on the round Dendara zodiac.

This map of the sky which divinities closely related to space and time support is made up of apparently concentric big circles. On the outer circle were drawn thirty-six figures whose hieroglyphic designations recall those of the decanal stars long ago used to mark the successive hours of the night. In the center of this map were drawn several circumpolar constellations : MSXtyw - the Big Dipper and c# Mwt - the Dragon. The intermediate space is filled with the twelve zodiacal constellations through which the five planets visible with the naked eye wander. A solar eclipse, a lunar eclipse as well, were also drawn (16).

The insertion of zodiacal constellations within Egyptian astronomical representations dates from the very beginning of the second century before our era, that is to say, from the Ptolemaic Period. Their drawing on the Dendara zodiac reveals the progressive integration of external cultural elements into traditional Egyptian representations.