Space Colonization (also called space settlement or extraterrestrial colonization) is the hypothetical permanent settlement and exploitation of natural resources at celestial objects other than Earth. As such it is a form of human presence in space, beyond human spaceflight and operating space outposts. Building colonies in space or in other planets would require a combination of many factors, including access to space, food, construction materials, e nergy, transportation, communications, life support, and others.