Phobos and Deimos in fiction Phobos and Deimos in fiction Mars has two moons, Phobos and Deimos. Due to their small size, both moons were discovered only in 1877, by astronomer Asaph Hall. Nevertheless, they frequently feature in works of science fiction. Some of the earliest mentions of Mars's moons in fiction predate their discovery. In Jonathan Swift's famous satire "Gulliver's Travels" (1726), the astronomers of flying island Laputa are described as having discovered two satellites of Mars. Voltaire's short story "Micromégas" (1752), about alien visitors from Sirius and Saturn, also describes Mars as having two moons. Voltaire is thought to have been influenced by
Moons of Mars infrared suggest a composition containing mainly phyllosilicates, which are well known from the surface of Mars. The spectra are distinct from those of all classes of chondrite meteorites, again pointing away from an asteroidal origin. Both sets of findings support an origin of Phobos from material ejected by an impact on Mars that reaccreted in Martian orbit, similar to the prevailing theory for the origin of Earth's moon. The moons of Mars may have started with a huge collision with a protoplanet one third the mass of Mars that formed a ring around Mars. The inner part of the ring