Ra was a star on the Ship of a Billion Years that held a deep and complex meaning to the Osirians. He was too complicated for the word "alive" to apply to him. The Osirians treated him with almost god-like reverence, though the idea of believing in gods was seen as distasteful. (AUDIO: The Ship of a Billion Years) The Great Houses interpreted Ra as an artificial sun, and the War King threatened to destroy him with their solar engineering technologies. (AUDIO: Words from Nine Divinities)
According to an Egyptian legend known by Erimem, Ra was a sun god who once lived among the Egyptians as a human. The queen of the Osirans, Sekhmet, was born from Ra's eye to slaughter Ra's enemies. Sekhmet herself referred to herself as "the eye of Ra". She said that her breath "created the desert" and over it, she sent Sutekh to rule.
Erimem said that killing Ra's enemies gave Sekhmet a taste for blood and began to kill all life. Ra ordered a high priest at Heliopolis to pour beer that was dyed with the juice of pomegranates as bait for Sekhmet. Sekhmet drank this lake of "blood" and became stupefied by the alcohol. She was trapped in a tomb of salt, or trisilicate, which the Fifth Doctor pointed out was a spaceship which was sent into space. Inside the ship, she was also bound by a blood lock, requiring the blood of four female royals. (AUDIO: The Bride of Peladon)