Solar System in fiction Solar System in fiction The Solar System and its various bodies (planets, asteroids, moons, etc.) were the earliest objects to be treated as fictional locations in works of science fiction. Among these, imaginary voyages to and explorations of Earth's Moon are found in seventeenth century literature. By the early twentieth century, following the increase in scientific and technological development spurred by the Industrial Revolution, fictional journeys to (or from) the Solar System's other planets had become common in fiction. Early literature regarding the Solar System, following scientific speculations dating back to the 17th century, assumed that every planet hosted its
Solar System largely of materials with lower melting points. The boundary in the Solar System beyond which those volatile substances could condense is known as the frost line, and it lies at roughly 5 AU from the Sun. The objects of the inner Solar System are composed mostly of rock, the collective name for compounds with high melting points, such as silicates, iron or nickel, that remained solid under almost all conditions in the protoplanetary nebula. Jupiter and Saturn are composed mainly of gases, the astronomical term for materials with extremely low melting points and high vapour pressure, such as hydrogen, helium,