Ceres

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Ceres was the smallest identified planetoid in the Sol system and the only one in the asteroid belt. It was discovered on January 1, 1801, and was named for the Roman Goddess of mythology. This was the first asteroid to be colonized by Humans.

The planet Ceres was named after this planetoid by a group of Humans who would later become known as the Ten Tribes of Ceres. (TOS novelization: Friday's Child)