From Halopedia, the Halo wiki
Shalimanda, known as the heaven-snake, was a legendary entity in the mythology of ancient humans living on Earth in the years prior to the firing of the Halo Array. It was said that one night Shalimanda had swallowed the original shining, jewel-encrusted stream of worlds. The next night, Shalimanda exploded, showering the sky with all the darker, earthy orbs on which humans would grow.
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