CANCER, which is Latin for crab, is the dimmest of the 13 constellations of the Zodiac, having only two stars above the fourth magnitude. Cancer is the faintest of the 12 zodiac constellations. Its symbol is ♋. The constellation was first cataloged by the Greek astronomer Ptolemy in the 2nd century.
In mythology, Cancer is associated with the crab in the story of the Twelve Labours of Heracles (represented by the Hercules constellation). In the myth, Hera sends the crab to distract Hercules while the hero is fighting the Lernaean Hydra, the serpent-like beast with many heads and poisonous breath, represented by Hydra constellation. When the crab tries to kill Hercules, Hercules kicks it all the way to the stars.
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