Benefits from out of this world

Benefits from out of this world

Acta Astronautica Vol. 19, No. 9, pp. 763-769, 1989 Printed in Great Britain 0094-5765/89 $3.00+ 0.00 Pergamon Press pie BENEFITS FROM OUT OF THIS W...

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Acta Astronautica Vol. 19, No. 9, pp. 763-769, 1989 Printed in Great Britain

0094-5765/89 $3.00+ 0.00 Pergamon Press pie

BENEFITS FROM OUT OF THIS WORLD# AMIT K. MAITRA International Directorate, Grumman Space Station Program Support Division, Reston, Va, U.S.A. (Received 31 May 1989) Abstract--This paper examines: (a) useful attributes of space; (b) progress in space technology, past and projected; and (c) benefits to be obtained from missions encompassing the LEO, GEO and lunar domains. In recent times, the attempt to explore space has been accelerated, not because it is there, but because its potential is needed. Today's man finds that potential to be most enticing and fortunate, as the leaders in space industry give it a little thought, for it makes the extra-terrestrial world theirs (space industry's) to develop, to utilize, and to commercialize. Also, from the standpoint of the average man, such efforts amount to taking a big leap forward in time, because it is essentially the road into the 3-dimensional civilization in which Earth becomes the center of a vast and growing sphere of human activity encompassing surrounding space and other worlds. Given such mission goals and domains, the scope and intent of this paper assumes a far greater degree of importance in that it brings to focus a legacy of aspirations, challenges, and an expanding list of benefits from man's own initiatives in space technology design, development, integration, and deployment.

I. INTRODUCTION Space science and technology, as it has evolved in the last several years, has profound social pertinence beyond its scientific and technological significance. Social pertinence refers to all activities connected with space beyond the biosphere that affect directly the public at large. The ultimate issue of space activities is not destination Moon or destination Mars but destination Man. The activities are, therefore, to contribute to problem solutions, meet the needs of people or provide outright improvements of life on the societal, domestic or global level. And social pertinence is the criterion by which one can place emphasis on benefits for the largest number of individuals, rather than a small group of scientific and engineering professionals. Now, the social potential of space science and technology is proportional to direct social pertinence of space activities. Such potential is proportional also to the speed and efficiency with which space activities of indirect social pertinence, namely, scientific and explorative space activities are given direct social pertinence. So there are two factors that determine the social potential of space technology: the direct social pertinence of space activities and the social convertibility from indirect to direct social pertinence. A high rate of social convertibility translates into a proportionately accelerated return on the investment made in research, development and exploration. Some observers tend to perceive Earth as isolated in "hostile" space, filled only with "forbidding" and "useless" worlds. Space scientists, on the other hand, tPaper IAA-88-565 presented at the 39th Congress of the International Astronautical Federation, Bangalore, India, 8-15 October 1988. A.A. 19/9--C*

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are intrigued with space and other worlds as a source of knowledge, and view space applications primarily as a scientific and technological challenge. There is a dichotomy in the above attitudes in that an adequate perception of either space potential or the needs of mankind on Earth is lacking. This dichotomy mitigates against effective social convertibility of the space potential, because it stifles the identification of needs and leads to public doubt about the worthwhileness of investing in a space program that is large enough to yield significant social benefits. If one views space activities as essentially a matter of science/technology and of small scale applications potential, one can obviously justify a small space budget. Clearly such a budget and the resultant program will have little pertinence to social needs. It will only be significant scientifically, technologically and socially and in that order of priority. The ultimate question that one must raise today is not whether or not a vigorous, socially as well as scientifically pertinent space activity can be planned realistically and implemented at a fraction of other national budgets. This can be done. The ultimate question is whether the public understands sufficiently the potential of space technology to want a socially pertinent space program. Here, at the risk of repeating, it needs to be pointed out that communications between the high technology of space and the user are not very open because of the gulf between specialized interests on one side and lack of perception of the potential usefulness of space on the other. This gulf must be bridged by those to whom the affairs of the people, on the national and global scale, are a matter of deep concern. For this reason, the aerospace professional, who cares to look beyond his engineering or scientific speciality, does not have to restrict himself to science and technology, leaving the

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goal setting to others. He can display broad responsiveness to the needs and the "option capital" of the national and global community. To that end, this paper is an attempt to underscore the reasons why the public should understand sufficiently the potential of space technology to want a socially pertinent space program. 2. SPACE ACTIVITIES: A MATTER OF BALANCE AND INTEGRATION

In the early 1970s, Dennis Meadows generated much enthusiasm among scholars by publishing his work on The Limits to Growth: A Report for the Club of Rome's Project on the Predicament of Mankind[l]. This was preceded by Jay W. Forester's Worm Dynamics[2] and followed by several other scholarly studies on the future of the future[3]. The conclusions of all of these world dynamics studies were based on the obsolescent concept of a closed world and on the faulty premise that this world will remain closed-limited to the biospheric shell of our planet. The fact of the matter is that the world of modern industrial man is no more closed than it is fiat. Space is a valuable environmental resource as well as the best possible link to other worlds and their raw materials--there lies an important answer to man's crisis of growth. Like all life, man must "exploit" to live. There can be no question that the more that space and other worlds can be used as industrial raw material source and disposal site within the limits of economic practicability, the more can Earth be returned to life, to human existence and to human development. The present technology on Earth is transient--not based on long-term capability or feasibility. For instance, power is generated from fossil fuels on Earth rather than from nuclear energy generated in space and beamed to Earth. What is more, present technology considers Earth as the only raw material base, as if no other raw material sources were within reach. Present technology is also based on Earth as the only place of production, even though production (by necessity, not ill will) is the main source of pollution (pollution due to consumption is lower, except in the case of transportation). In short, our present technology on Earth is based on technologies which cannot provide the necessities for mankind cost-effectively in the long run. In recent times it has become commonplace to hear such proclamations as that human growth must aim at nothing less than the achievement of a humane living standard for all. In that context, space technology promises a level of improvement that surpasses all human expectations. By utilizing space technology, it is possible to devise a global development program whose central premise is the indivisibility of Earth and space (including other worlds). This indivisibility has dual significance. On the one hand, it ensures:

Table 1. Useful attributes of space Weightlessness (facilitates special manufacturing activities, construction of very large delicate structures, and reliability of operations) Easy gravity control Absence of atmosphere (unlimited high vacuum) Comprehensive overview of Earth's surface and atmosphere, for communication, observation, power transmission, and other applications Isolation from Earth's biosphere, for hazardous processes: little or no environmental, ecological or "localism'" issues Readily available light, heat, power (10 times rate on Earth) Infinite natural reservoir for disposal of waste products and safe storage of radioactive products Super-cold temperatures (infinite heat sink near absolute zero) Large, 3-dimensional volumes (storage, structures) Variety of nondiffuse (directed) radiation (u.v. X-rays, y rays, etc.) Magnetic field Availability of extraterrestrial raw materials on Moon and possibly on asteroids Avoidance of many Earth hazards (storms, earthquakes, floods, volcanoes, lightning, unpredictable temperatures and humidity, intruders, accidents, corrosion, pollution, etc.) Potentially enjoyable, healthful, stimulating or otherwise desirable for human well-being Source: J. Von Puttkamer, The long-range future. In Space Stations and Space Platforms--Concepts, Design, Infrastructure, and Uses (Edited by I. Bekey and D. Herman), Vol. 99, Prog. Astronaut. Aeronaut. American Institute of Aeronautics and Astronautics (1985).

(a) A broadening of mankind's resource base. (b) Development of advanced technologies in the service of mankind, free of biospheric constraints and social complications. (c) Gradual separation from Earth of geo-incompatible production processes. On the other hand, it generates new hopes for the integration of geo-incompa.!ible industrial processes into the terrestrial cycles--a benign industrial revolution minimizing pollutive and biocidal side effects and requiring global management with extensive use of satellites and Space Stations. Table 1 provides a listing of major attributes of space that make it attractive for various types of industrialization[4,5]. Here, one must be made aware of the fact that the issue is not only space but Earth as well. Mankind's future rests on a strategy of balanced, synergistically integrated developments on Earth and in space. It is precisely such strategic integration that can allow twentieth century man to cope with the environmental problems of the industrialized nations, the production problems of the developing nations and with the resource problems of both. In other words, the type of strategic integration being conceived here allows mankind to grow and live through open-world development which contains all the futures the human mind can hold. 3. LONG-RANGE TECHNOLOGICAL PREREQUISITES

Technology in space and its foundations, space technology, give us these unique options. Some will become possible and necessary before this century draws to a close. Table 2 summarizes progress in space technology, past and projected[6]. Again, these space technology developments must be put in the

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Table 2. Progress in space technology, past and projected System 1975 1990 2000 1. Launch vehicle 250,000 80,000 10~ payload (Ib) capability reusable reusable 2. Communication 15,000 100,000 10 7 channels (GEO) (GEO) (GEO) 3. Communication l0s 10 7 10 9 bit rate (Mars-Earth) 4. Mission, length 250 l0s 5 × 105 (man-days) 5. Resolution (km) 0.1 0.05 0.02 (GEO) (GEO) (GEO) 6. Data storage 2000 I/2 10 times on-board books Library of Library of (20 Gbits) Congress Congress (8000 Gbits) 7~ Energy storage 40 800 1200 (kWh/|b) 8. Active circuits 120,000 5 x 10s 10~°-10~2 (per in3) 9. On-board computer 0.5 x 106 30 x l0s 100-1000x 106 speed (operations/s) 10. Launch cost 3000 1000 100-300 19845/1b to LEO 111 Position error (m) 50 0.1 0.02 12. Failure rate 10 4 10-6 10-7_10-8 Notre: Adapted largely from NASA Technology Forecast Report[6].

proper context, namely, the social--economicecological pertinence of space activities. Early in t h e 1970s, the late Dr Kraft Ehricke espoused the concept of m a n - p l a n e t conflict pattern [7]. This concept is still very useful in that it underlies the manifold crises of the remaining decade(s) of this century: Figure 1 is a. brief and unavoidably simple depiction of the concept. As shown here, there are four basic conflict elements: --pollution --information/traffic congestion --energy --minerals. These are traced qualitatively in terms of conflict severity vs time over a period of two centuries. Conflict severity, also as shown in the figure, has four levels: Level I

Level II - - r e q u i r e s some accommodation? Level III --signifies a much more difficult accomm o d a t i o n process:~ Level IV ----outright confrontation without possibility o f accommodation in the existing frame of reference.:~ Pollution (biospheric/environmental destruction) and traffic congestion through ecologically (though not necessarily economically) unsound population distribution patterns and associated need for information give rise to the first two basic conflict elements. These conflict elements, as various past and present analytical treatises[7-10] indicate, could reach Level IV conditions even before this century is up, if the conflict elements are allowed to continue unabated. The third and fourth basic conflict ktlttR IITATION

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~'The term accommodation indicates that some changes are necessary. These may range from the level of monitoring and legal measures to technological improvements or adoption of alternate methods. :~This involves societal (legal/social/habit pattern oriented), economic and even political adjustments that are no longer insignificant. Environmental damage is severe but not yet irreparable, although different natural equilibria than in the past might evolve. §This leads either to irreparable biospherical damage seriously affecting the future viability of this planet, or else forcing man to "back down" significantly and submit to strict limitations in his further evolutionary pattern by environmental dictate.

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elements--energy and minerals--are also headed for Level IV conditions. Granted, these will not be depleted until a later time, but that possibility is still within a relevant future, placing them within the range of our concern. Figure 1 shows how a number of techno-scientific key measures could reduce the upward trend of the conflict elements and ultimately, can turn them downward as new long-range solutions are developed. Again, the purpose of the illustration is to show the trend in the evolution of those contributions that space can make in the larger context of terrestrial and extraterrestrial advances to overcome the problems indicated by the confrontations. Vertical bars in the figure indicate the required space capability. Regarding these space capabilities, almost all involve the utilization of space through satellites or through more advanced facilities in orbit and on other celestial bodies. For instance, through navigation and traffic control satellites, information transmission will ameliorate many of the traffic problems. Through information transmission satellites, the economy-based need for heavy population concentrations will also be reduced. Such trends toward a more desirable population distribution and toward reduction of traffic congestion can be promoted further by the use of light from space through the use of sunlight reflectors in geosynchronous orbit. The solar reflectors actually affect the first three of the four conflict elements identified by the man-planet conflict pattern. These conflicts are predominantly the issues with which the societies in Third World countries are concerned today. Given the location of this year's Annual I A F Conference in Bangalore, India as well as the limited space in which to cover a whole range of topics on a subject that is still not very well understood, it is perhaps highly appropriate to limit our discussion in this paper to a single example, the enormous benefits to be obtained from the design, development, and deployment of sunlight reflector technology. This discussion might throw some light on the types of possibilities that lie ahead for mankind. Before one actually undertakes such a systematic and comprehensive discussion of sunlight reflector technology, one must also investigate the space technology development sequence, the integrated requirements, and the desired attributes of the particular orbit of a reflector. To that end, the following sections set forth the details in terms of the Plateau of Departure, Desired Attributes, Space Science and Technology and Applications Missions, and finally Beyond Earth Services: Value Generation. 4. PLATEAU OF DEPARTURE

In terms of broader technological evolution in space, one can consider the Space Station as both a plateau in human progress and a major nodal point in time. Its deployment makes possible, among other

things, earth applications, including sustained R&D for the conception and development of innovative systems and techniques currently not available, not understood or unknown. Table 3 lists some of those potential applications with reference to their relevance to mankind's materialistic, intellectual, and humanistic goals and/or needs. The column on the right also attempts to identify the most likely space domains involved in meeting these needs. 5. DESIRED ATTRIBUTES

It is apparent from the above table that major manned and automated space missions that will provide unprecedented scientific/technical benefits can be envisioned in low Earth orbit (LEO), geosynchronous orbit (GEO), and also in other high-energy orbits, including lunar orbit and lunar surface and beyond. The ultimate location for the most effective utilization of a man-tended space system, however, appears to be in GEO. There are several reasons for this, but the two most important special features of a geosynchronous site are the following: (1) From the vantage point of the geosynchronous or 24-h orbit, almost one-half of the globe is in view at all times. (2) The observer, in the plane of the Earth's equator, remains essentially fixed over a given meridian. Because of these reasons, millions of Earth-based users can be serviced by one or only a few satellite platforms in GEO. 6. SPACE SCIENCE AND T E C H N O L O G Y AND A P P L I C A T I O N S MISSIONS

With reference to these missions, it is pertinent to identify and differentiate the type of space activities that give rise to various potential services. These activities can be variously grouped under: --generally innovative - - E a r t h services --space value generation. The first group comprises space science programs, advances in high technology and technological/ managerial spin-offs. The other two groups have direct social pertinence. Earth services involve mostly supporting activities for information transmission, atmospheric observations, and surface observations. People, in general, recognize that Earth services are of vital social importance. They know for instance, that conversion from science and technology to direct social pertinence has progressed most successfully in the fields of communication and meteorology. In the matter of surface observation, however, there are a wide variety of applications. These have generated: --ambiguous user delineations ---overlapping responsibilities.

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Table 3, Post Space Station mission goals vs domains Benefits Type* Domain involved Determine solar system I LEO and solar origin/early history system probes Understand galactic I LEO and solar structure/dynamics system probes Understand cosmology I LEO and solar system probes Verify physical laws I LEO and solar system probes New resources from space M Lunar surface/Mars moons/asteroids Commercialization Optimizeindustrial M LEO and GEO activity Hazard removal M LEO, GEO and cislunar space Energy from space M GEO/cislunar space New resources from space M Lunar surface/Mars moons/asteroids Earth applications Agriculture,forestry, M LEO and GEO fishery management Protect environment H LEO and GEO Aid individuals in peril H LEO and GEO Aid crime control H LEO and GEO Aid internal security H LEO and GEO Improve government H LEO and GEO Energy from space M GEO/cislunar space New resources from space M Lunar surface/Mars moons/asteroids International cooperation H LEO and GEO lunar base, Mars missions Expanding human Space habitation H LEO and GEO opportunities lunar base, Mars missions New technological M LEO and GEO capabilities lunar base, Mars missions New resources from space M Lunar surface/Mars moons/asteroids Hazard removal H LEO, GEO and cislunar space International cooperation H LEO and GEO lunar base, Mars missions Promote international H LEO and GEO peace and lunar base, Mars missions M *I, Intellectual; M, materialistic/utilitarian; H, humanistic. Source: J. Von Puttkamer[5]. Goals Science and exploration

Together, these factors inhibit the d e v e l o p m e n t of a user market. T o m o s t observers, the social benefit of E a r t h services, therefore, ( l ) m e a n s better E a r t h d a t a collection, a n d (2) has little significance in terms o f intrinsic space value generation. Clearly, this is a misconception. The social benefit o f E a r t h services c a n n o t be u n d e r s t o o d o n the basis o f d a t a collection only. This subject m a t t e r is so involved t h a t it c a n n o t be fully covered in a brief p a p e r o f this scope. Instead, the reader is referred to the early works o f the late D r K r a f t Ehricke[7-9]. 7. BEYOND EARTH SERVICES: VALUE GENERATION

O n the question of space value generation, it should be n o t e d t h a t in a n E a r t h - o r i e n t e d space tThe first phase includes not only the technological achievements in the form of Shuttle, Space Station, geospace transport and low-cost satellites, but also the managerial and procedural aspects in organizing maximum global participation in using the information and capabilities offered for national improvement and global development.

p r o g r a m , E a r t h services merely represent the first p h a s e . t T h e second phase will a d d value generation to E a r t h services in geospace a n d e x p a n d o p e r a t i o n s to l u n a r o r b i t a n d the l u n a r surface using space station core modules in LEO, G E O , a n d l u n a r orbit. Value generation, as differentiated from E a r t h services, designates all those processes t h a t generate goods r a t h e r t h a n services. Value generation implies the processing of energy or material in space, r a t h e r t h a n the processing of i n f o r m a t i o n as with E a r t h services. Processing refers to the processing o f solar r a d i a t i o n for the purpose of illumination or heating of selected p o r t i o n s of the E a r t h ' s surface. T h e most suitable orbit for energy processing appears to be G E O . A key technology for the i l l u m i n a t o r (the space light) is solar reflector technology[7] a n d there are m a n y E a r t h - o r i e n t e d applications o f the illuminator. Figure 2 catalogs these applications. T w o o f the m o s t p r o m i s i n g applications t h a t we m i g h t witness in o u r time are the illumination of large u r b a n areas a n d the s u p p o r t to agricultural activities. T o facilitate such applications, the basic design requirements of the reflector are going to be low

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mass, good controllability, and high illumination versatility. These requirements, as shown in Fig. 3, are met by a spider web structure to which reflector facets are fastened. This way they can rotate about one exis in the plane of the reflector. Each facet consists of a very low-weight frame holding a highly reflective metal foil. The facets are turned as a function of distance from the center, so as to concentrate the light into the image footprint. They can also be turned around, orienting a non-reflective

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backside toward the sun. Thereby it is possible to "overdimension" the illuminator. Outer row of facets can be "turned off" on clear nights and, again, on clouded nights the light power of the reflector can be similarly increased by turning additional facets into position. The entire system of facets and the reflector position can be computer controlled (with emergency override from space station and/or ground control), to optimize its illuminating function. The facets can be exchangeable. Routine maintenance and repair can be performed by teleoperators, so that only peiodic manned inspection and maintenance would be required. Now, the size of the reflected solar image on Earth is going to be a function of the focal distance. At geosynchronous altitude, the diameter of the image "footprint" is approximately 320 km (181 n.mi)[7]. This should create diffuse, gentle, natural, not overly intense lighting that establishes immediate compatibility with animal life and illuminates large areas at uniform level rather than imposing the sharp variations in intensity of ordinary street lighting. Full moonlight at a clear night has an intensity of about 0.1 lx (10 -2 lumen/ft'). A reflector of 1.6 km 2 or about 17 million ft 2 (0.61 sq. miles) of reflector area

Benefits from out of this world (4700 ft 2 dia, if circular), stationed in geosynchronous orbit over the equator, could produce a maximum illumination of about 10 times this intensity. A moderate cloud cover reduces surface illumination by the Moon by only a factor of about 2 and heavy overcast by a factor of about 6. In view of this fact, a Lunetta (Illuminator) of the size given above would illuminate an area under heavy overcast still more brightly than the full Moon on a cloudless night. These technological possibilities derived from extraterrestrial applications concepts are but a few of the answers for the society of the future. Any recent studies of the World Bank, United Nations Development Program or any other multinational systems research institute would confirm that cities are expanding into ever larger metropolitan areas. Thus, emphasis on large area illumination may increase. Space light is one approach which can meet this growing need without the consumption of vast amounts of materials for cables and lighting structures; and can provide a uniform light level that could not be matched by electric lighting without vast expenditure of electric power. Both factors are of great importance ecologically in industrial nations. By the same token, they are of great importance economically and ecologically for densely populated areas in developing countries. Through night illumination, agricultural activities (sowing or harvesting) can also be performed at night. This, again, is particularly valuable in developing countries and in warm regions of Earth where work in the coolness of night provides welcome relief and can actually be performed if there is adequate illumination. Night illumination, coupled with long-range weather forecasting, has the further potential of accelerating harvest activities prior to inclement weather, reducing crop losses. The illumination program is one example of the many extraterrestrial science and technology applications missions. Space power is another promising area of space value generation. Space Station and cost-effective interorbital transportation to geosynchronous orbit can eventually bring into reach still more ambitious concepts of space value generation in the open space environment. Both Space Light and Space Power require extensive LEO test programs and very large structures in GEO. They cannot be set up without a combined human and teleoperator construction crew whose base of operation will most likely be an enlarged space station of the types conceived by the U.S.A. and the U.S.S.R. supplemented by intermittently inhabited modules in geosynchronous orbit near the construction site.

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To sum up, one can only say that perhaps, as we place the LEO, GEO and other outer space domains into the service of all people, we may be---just may be--able to hope for the greatest benefit of all: that the ugly, the bigoted, the hateful, the cheapness of opportunism and all else that is small, narrow, contemptible and repulsive would become more visible and far less justifiable and tolerable from the vantage point of the stars than it ever was from the acute angle of the mudhole. Should we not take a cue from Bertrand Russell, who in his book Has Man a Future[ll], urged us to "consider the poets, the composers, and the men whose inward visions have been shown to the world in edifices of majestic splendor?" After all, these are the men whose creative urges have often demonstrated that Man has placed his dreams and aspirations among the stars and his nightmares into caves whence he came! Acknowledgements--This paper is dedicated to the memory

of Dr Kraft A. Ehricke, who urged me to write this back in 1974, I also thank my colleague Edward Grenning for his helpful comments on the initial draft of this paper. REFERENCES

1. D. H. Meadows and L. Dennis, The Limits To Growth: A Report For the Club of Rome's Project on the Predica-

ment of Mankind. Universe Books, New York (1972). 2. J. W. Forester, Worm Dynamics. MIT, Cambridge, Mass. (1969). 3. E. Owens and R. Shaw, Development Reconsidered. Heath, lexington (1972). 4. J. Von Puttkamer, The industrialization of space: transcending the limits to growth. In Global Solutions-Innovative Approaches to Worm Problems. World Future Society, Bethesda, Md (1984). 5. W. M. Brown, Private communication referenced in J. Von Puttkamer, The long-range future. In Space Stations and Space Platforms--Concepts, Design, Infrastructure, and Uses (Edited by I. Bekey and D. Herman), Vol. 99, Prog. Astronaut. Aeronaut. American

Institute of Aeronautics and Astronautics (1985). 6. A forecast of space technology, 1980-2000. National Aeronautics and Space Administration, NASA SP-387 (1976). 7. K. A. Ehricke, Statement to the Committee of Science and Astronautics, House of Representatives, Congress of The United States, 1973 NASA Authorization, 92nd Congress, Second Session, No. 15, Part 2, U.S. Government Printing Office, H.R. 12824. 8. K. A. Ehricke and E. Miller, The extraterrestrial imperative, from dosed to open world. Copyright (1971). 9. K. A. Ehricke, Earth environment and resources management from space. Presented to XXI1 International Astronautical Congress, International Academy of Astronautics, Brussels, Belgium (1971).

10. K. A. Ehricke, A case for space. Presented to the Citizens Campaign For Space, sponsored by The Center of American Living Inc., NYC, N.Y. (1970). 11. B. Russell, Has Man A Future. Simon & Schuster, New York (1961).