Chiron is called a centaur because he is born half man and half horse. His form came about because his father, Chronus, had mated with his mother, Philyra, in the shape of a horse. Chiron was born immortal. Unlike most centaurs who were mean and ruthless towards humans, Chiron was always kind and gentle towards them.
Chiron was famous for his wisdom and knowledge of music, medicine and ethics. The idea of surgery came about, according to the story, when Chiron replaced a damaged bone in Achilles' ankle with a section from the ankle of a giant.
At the Massacre of the Centaurs, the mean centaurs were pursued and killed by Heracles's magic bow. Chiron, who was standing by Heracles, unfortunately, was accidentally wounded in the knee by his magic arrow. Although Chiron was skillful in medicine, he could not heal a wound from Heracle's magic arrow. The wound was extremely painful and he retreated to a cave.
He pleaded with Zeus to take away his immortality
so that he could die. Zeus granted his wish. Chiron was placed
among the constellations as Sagittarius, the Archer. So when you
look up at the night sky, you will see Chiron.