Naming of moons to as "Proserpina". More recently, especially in science-fictional contexts, the Moon has been called by the Latin name "Luna", presumably on the analogy of the Latin names of the planets, or by association with the adjectival form "lunar". In technical terminology, the word-stems "seleno-" (from Greek "selēnē" "moon") and "cynthi-" (from "Cynthia", an epithet of the goddess Artemis) are sometimes used to refer to the Moon, as in "selenography, selenology," and "pericynthion." The moons of Mars (Phobos and Deimos) were named by Asaph Hall in 1878, soon after he discovered them. They are named after the sons of the god
Moons of Mars satellites, Earth had one and Jupiter had four (known at the time), that Mars by analogy must have two. Furthermore, as they had not yet been discovered, it was reasoned that they must be small and close to Mars. This would lead Swift to making a roughly accurate estimate of their orbital distances and revolution periods. In addition Swift could have been helped in his calculations by his friend, the mathematician John Arbuthnot. Voltaire's 1752 short story "Micromégas", about an alien visitor to Earth, also refers to two moons of Mars. Voltaire was presumably influenced by Swift. In recognition of