Mars to Stay to 30, thereby beginning a Martian settlement. Since the Martian surface offers all the natural resources and elements necessary to sustain a robust, mature, industrialized human settlement—unlike, for example the Moon—a permanent Martian settlement is thought to be the most effective way to ensure that humanity becomes a space-faring, multi-planet species. Through the use of digital fabricators and in vitro fertilisation it is assumed a permanent human settlement on Mars can grow organically from an original thirty to forty pioneers. A Mars to Stay mission following Aldrin's proposal would enlist astronauts in the following timeline: As Aldrin has said, "who
Earthling English "yrþling", in the meaning "ploughman". The sense of "inhabitant of earth" is first attested in the 1590s. Its use in science fiction dates to 1949, in "Red Planet" by Robert A. Heinlein. The word "Human" has the same imposed meaning, since it originates from a PIE word "*ǵʰmṓ" "earthling" < "*dʰéǵʰōm" "earth". Compare Latin "homo" "human" and "humus" "earth, soil". Its modern use in science fiction literature contrasts "Earth" (the planet) with outer space or hypothetical other planets with sapient life. The term was often used in 1950s science fiction film and novels by aliens to express a disdainful