Ouranos was the god which personified the sky in ancient Greek mythology. Together with the mother of the Earth, Gaia, Ouranos fathered the Titans as well as the hundred-handed Hecatoncheires, whom he imprisoned in the pit below Hades, Tartarus. Some stories also claim Gaia fathered Ouranos, as well, as Gaia is usually considered the only entity to have emerged from the Chaos, a Greek term used to describe the void that existed prior to the current universe.

According to myth, prior to the creation of this world, the sky and earth (Ouranos and Gaia, respectively) came together each day, making love and creating children, who existed in the dark space in between them. It was only after the events of the creation myth that the sky became fixed above the earth, as it is today.
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