The Arrow in the SkySagitta is a small constellation, but the bow and arrow was a common weapon in classical times. Therefore it should not be surprising that there are different stories to account for the presence of an arrow in the sky.
Apollo's ArrowAccording to one tale, the Arrow belows to Apollo. Apollo was associated with the sun, also with wisdom and truth. He was known for his good looks as well. The son of Apollo was the God of Healing, known as Asclepius. The Arrow in this version is an instrument of revenge.
Getting Rid of the DoctorAclepius had the power to heal even the dead, returning them to life again. The God of the Underworld complained to Zeus. He was no longer gaining subjects for the Realm of the Dead. Zeus listened to the Ruler of the Dead and struck Asclepius dead with a thunderbolt.
Apollo's RevengeZeus's weapons, his armory of thunderbolts and lightning flashes had been forged by the three monstrous one-eyed Cyclopes. It is said that in revenge for the loss of his son, Apollo slew the Cyclopes with an Arrow, which is the Arrow that we see in the sky in the form of Sagitta.
Hercules' ArrowIn another story the Arrow is identified with the great hero Heracles (Hercules). This is the Arrow with which Heracles slew the eagle pecking at the liver of Prometheus. Prometheus had been punished by Zeus for giving human kind the gift of fire. He was chained to a rock in the Caucausus Mountains to be tormented by an eagle pecking eternally at his liver. Prometheus was released when the immortal Centaur Chiron agreed to accept death in order to save Prometheus. But first Heracles had to slay the eagle. It is to commemorate Heracles' feat that the Arrow is placed in the sky.
Eros' ArrowA third story identifies the Arrow with Eros, the God of Love. It was this Arrow that ignited the passion of Zeus for the young boy Ganymede, whom Zeus had abducted to Mount Olympus to serve as the Cup Bearer to the Gods. The constellation of Aquarius is also identified with Ganymede. And in the constellation of Aquila, we see the Eagle of Zeus bearing Ganymede in his claws.