Hemera primordial Goddess of the day

Hemera was the the primordial goddess (protogenos) of the day. She was a daughter of Erebos (Darkness) and Nyx (Night) and the sister and wife of Aither (Aether, Heavenly Light).

Every evening Hemera's mother Nyx drew her dark veil across the sky, obscuring the the shining blue of the heavenly ether (aither), and bringing night to earth. With each morn Hemera dispersed her mother's mists, bathing the earth again in the light of the ether. In the ancient cosmogonies night and day were actual substances distinct and independent of the sun. The sun ruled the day but was not its source.

Hemera was closely identified with Hera, the queen of heavens, and Eos, the goddess of the dawn. Hesiod seems to regard her as more of a divine substance rather than anthropomorphic goddess. She was largely irrelevant in mythology, with her role being entirely subsumed by the goddess Eos.