Hydra (moon) the Hydra, the nine-headed serpent that battled Heracles in Greek mythology. The nine heads of Hydra are a reference to Pluto's tenure as the ninth planet; its initial, "H", refers to the Hubble Telescope, which discovered Hydra and, together with Nix, to the "New Horizons" mission whose safe passage was the motivation for taking the Hubble images. Hydra orbits the barycenter of the system in the same plane as Charon and Nix, at a distance of about 65,000 km. Its eccentricity of 0.0059 is small, but significantly non-zero, and the largest of those of Pluto's small moons (slightly larger than
Greek mythology in western art and literature works of Ovid, Greek myth influenced medieval and Renaissance poets such as Petrarch, Boccaccio and Dante in Italy. In northern Europe, Greek mythology never took the same hold of the visual arts, but its effect was very obvious on literature. Both Latin and Greek classical texts were translated, so that stories of mythology became available. In England, Chaucer, the Elizabethans and John Milton were among those influenced by Greek myths; nearly all the major English poets from Shakespeare to Robert Bridges turned for inspiration to Greek mythology. Jean Racine in France and Goethe in Germany revived Greek drama. Racine reworked