Sagittarius myth, i.e., the mythology of Sagittarius the Archer, 9th among 12 zodiac signs is connected with the centaur Chiron. Being half-horse, the centaurs were categorized as bestials. But the Greeks valued their horses a lot and hence centaurs were regarded somewhat higher than the rest of the bestials.
Especially Chiron had a great goodwill of being a gentle and a talented centaur. He was a master of multifarious talents like archery, music and medicine. That was why he was appointed as a tutor to the likes of Achilles, Jason, and Hercules.
As it happened that Hercules accidentally shot Chiron wounding him fatally since the arrow was a poisoned one and there was no medicine that would alleviate the pain. But being an immortal, Chiron couldn’t die peacefully as well.
In such a scenario, Chiron offered himself to the gods as a substitute for Prometheus whom they had punished by chaining him to a rock for giving fire to man. Everyday an eagle came and ate up his liver, which grew again as the night fell… to be devoured by the eagle again!
Hercules had already appealed to Jupiter for mercy, which he had agreed to provide a suitable substitute for Prometheus could be found in order to set him free. As Chiron replaced Prometheus giving up his immortality, Jupiter placed him into stars in recognition of his goodness and immortality.
This is how the Sagittarius myth, i.e., the mythology of Sagittarius the Archer, 9th among 12 zodiac signs goes according to what the Greek legend says. The constellation lies between those of Ophiuchus and Capricornus, Ophiuchus lying to its west and Capricornus to the east.