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 ==Chapter 4: Nonterrestrial Utilization Of Materials: Automated Space Manufacturing Facility==

4.1 Introduction
The heavens have always been the subject of intense curiosity and longing, beckoning to our imaginations and, sometimes, to our desires for dominion over that which is not yet under human control. Recent American space exploration efforts represent only tentative steps toward increased human understanding of the Universe - indeed, lunar and planetary missions often have raised more questions than they have answered. Those in the forefront of space sciences believe that the ultimate horizons are as yet only dimly perceived. A substantial minority of the American public would like to see more effort devoted to deeper investigations of the planets, stars, and galaxies beyond Earth.

However, most people remain unconvinced that expanded activities in space gained apparently at the expense of other societal goals are worth the price (Overholt et al., 1975). Clearly, future large-scale American space projects should embody a fundamentally new perspective - an overall shift from the existing policy of (primarily) exploration to one of integrated and direct utility for mankind. Such a pragmatic space utilization program may demand extensive use of nonterrestrial materials and an ever-increasing dependence on automation in all its dimensions. The Nonterrestrial Utilization of Materials Team has explored the need for such a program, and has laid the foundation for future NASA technology planning by examining in some detail a space project having the potential for physical growth with continually decreasing net materials import from Earth.

4.1.1 Objectives
A principal objective of the present study is to develop scenarios which show how, starting from current plans and capabilities, an extraterrestrial facility providing economic benefits for humanity can be established, maintained, and expanded in the near future. Ultimately, this permanent orbital factory will be dependent in large degree on nonterrestrial materials and autonomous robots programmed for advanced machine chapter 4 is to demonstrate the relationship between nonterrestrial utilization of materials and the growth of an orbital manufacturing facility beginning with a minimal "starting kit" of machines. The kit performs basic manufacturing processes necessary for facility expansion and the creation of a widening spectrum of the means of production.

This goal was chosen because only through the development of extraterrestrial resources can future space activities be pursued independently of terrestrial resource limitations and management constraints. The proposed scenarios for space facility maturation are essentially open-ended, so a variety of exploration and utilization options continuously become available once initial economic productivity is established.

The basic requirement explored in this approach to space industrialization is the establishment of two off-Earth facilities, one in space and one on the Moon. In this scenario, an Earth-orbital base will provide logistical support and production capability necessary for the creation of useful end products and its own expansion. A space platform should be established early, initially dependent on the Space Shuttle, as a demonstration of "starting kit" operation and advanced production methods. However, rapid factory growth necessitates the use of lunar or asteroidal resources. Therefore, a lunar processing and manufacturing facility (Dalton and Hohmann, 1972), possibly self-replicating (see chapter 5), is presupposed in the growth scenario.

The availability of nonterrestrial materials could make possible a decreasing dependence on Earth-based supplies. Growth of the Space Manufacturing Facility (SMF) subsequently would require no major additional Earth resource inputs. Given a supply of sufficiently inexpensive nonterrestrial materials, SMF output could be returned to Earth directly in the form of useful commercial products or indirectly in the form of solar power generation or satellite servicing.

The present analysis is explicitly guided by the goal of maximizing the use of automation and robotics during expansion of the processing and manufacturing facilities. Even in the early stages many operations can be conducted by remote teleoperators. As research in robotics continues, more and more system functions will be taken over by autonomous robots. While it is unlikely that the human presence soon can be completely eliminated, economic arguments favoring SMF deployment require the assumption of an increasing use of autonomous machine systems.