Dragon of the Giant-War
THE DRAKON GIGANTOMAKHIOS (Dragon of the Giant-War) was a huge serpent thrown at the goddess Athena by the giants. She caught it up and impaled it upon the pole of heaven to form the constellation Draco.
Draco was usually identified as the Hesperian dragon, guardian of the golden apples of the Hesperides.
Probably GAIA, though nowhere stated
CLASSICAL LITERATURE QUOTES
Pseudo-Hyginus, Astronomica 2. 3 (trans. Grant) (Roman mythographer C2nd A.D.) :
"Constellation Serpent . . . Some also say this Draco (Dragon) was thrown at Minerva [Athene] by the Gigantes, when she fought them. Minerva [Athena], however, snatched its twisted form and threw it to the stars, and fixed it at the very pole of heaven. And so to this day it appears with twisted body, as if recently transported to the stars."
- Hyginus, Astronomica - Latin Mythography C2nd A.D.