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 Greek mythology in western art and literature With the rediscovery of classical antiquity in the Renaissance, the poetry of Ovid became a major influence on the imagination of poets and artists, and remained a fundamental influence on the diffusion and perception of Greek mythology through subsequent centuries. From the early years of the Renaissance, artists portrayed subjects from Greek mythology alongside more conventional Christian themes. Among the best-known subjects of Italian artists are Botticelli's "Birth of Venus" and "Pallas and the Centaur", the Ledas of Leonardo da Vinci and Michelangelo, and Raphael's "Galatea". Through the medium of Latin and the