A semi-accurate star map: an analysis of the Athens zodiac circle

Within the collection of the National Archaeological Museum in Athens is a small marble plaque from ancient Egypt engraved with a circular depiction of the night sky and the signs of the zodiac (inventory number: ΝΑΜ ΑΙΓ 109). Very little work has been undertaken to analyse this artefact, and very little has been published about it. It has been suggested that the Athens ‘Zodiac Circle’ is a copy of a much larger representation of the night sky, such as the Dendera Zodiac which is now in the Louvre in Paris. However, a careful and critical comparison of these two relief carvings demonstrates that the one in Athens cannot be a copy of the Dendera Zodiac. Furthermore, an analysis of aspects such as the orientation of the constellations, their azimuth and altitude angles, and their angular size, as they are depicted on the Athens Zodiac circle, shows that one half of the engraving is more accurately rendered than the other. Further analysis shows that this is due to the Athens Zodiac Circle being a representation of the midnight sky on one of the most important days of the ancient Egyptian year – the beginning of the Summer Solstice.