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 and the Near East. Adonis seems to be the Greek counterpart—more clearly in cult than in myth—of a Near Eastern "dying god". Cybele is rooted in Anatolian culture while much of Aphrodite's iconography may spring from Semitic goddesses. There are also possible parallels between the earliest divine generations (Chaos and its children) and Tiamat in the "Enuma Elish". According to Meyer Reinhold, "near Eastern theogonic concepts, involving divine succession through violence and generational conflicts for power, found their way ... into Greek mythology". In addition to Indo-European and Near Eastern origins, some scholars have speculated on the debts of Greek