Sopdet (Sepdet, Sothis) personified the 'dog star' Sirius. This
star was the most important of the stars to the ancient
Egyptians, and the heliacal rising of this star came at the time
of inundation and the start of the Egyptian New Year. As a
Goddess of the inundation, she was a Goddess of fertility. She
also was linked to the pharaoh and his journey in the afterlife.
She was represented as a woman with a star on top of her head
dress, or as a seated cow with a plant between her horns as
depicted on an ivory tablet of King Djer. The plant may have
been symbolic of the year, and thus linking her to the yearly
rising of Sirius and the New Year. She was very occasionally
depicted as a large dog, or in Roman times, as the goddess Isis-
Sopdet, she was shown riding side-saddle on a large dog. Source:
Sopdet, Goddess of Sirius, New Year and Inundation by Caroline
Seawright