
Each year, after a stretch of invisibility, the lamp returns just before dawn. Egyptian observers used that heliacal rising as a calendrical mark, close to the season of the Nile’s inundation. The goddess Sopdet is already named in the Pyramid Texts of the late Old Kingdom as a celestial figure bound to the king’s rising. That is an Egyptian office, not a Greek dog and not a modern binary.
Sopdet’s identification with Isis is later. The physical star, the goddess Sopdet, Isis, and the name Sirius are different historical layers. They must not be collapsed.
Pyramid Texts, utterances naming Sopdet. R. O. Faulkner, The Ancient Egyptian Pyramid Texts (Oxford: Clarendon Press, 1969). Photograph: Brooklyn Museum Archives, lantern slide of Unas, Saqqara.











