000 years and involving searches of 1,000,000 target stars to distances of about 1000 light years in the Galactic Disk ..." and states that interstellar probes will be superior to beacon signals in the search for extraterrestrial intelligence.
The Space Exploration Team was charged with defining a challenging mission for the next century which could be a technology driver in the development of machine intelligence and robotics. Interstellar exploration was early identified as the ultimate goal, where this would focus on an investigation of planetary systems in the solar neighborhood discovered through SETI operations or by searches with large apodized visual telescopes (Black, 1980) in Earth orbit. Though previous studies of interstellar exploration missions are few, even these clearly suggest the need for high levels of automation.
The Team defined a general concept of space exploration centered on the notion of an autonomous extrasolar exploratory machine system. This system incorporates advanced machine intelligence and robotics techniques and combines the heretofore separate and manpower-intensive phases of reconnaissance, exploration, and intensive study into a single, integrated mission. Such an automatic scientific investigation system should be useful in the exploration of distant bodies in the Solar System, such as Jupiter and its satellites; Saturn and its rings; Uranus, Neptune, Pluto and their moons; and perhaps comets and asteroids as well. It may provide tremendous economies in time, manpower, and resources. Interstellar exploration seems virtually impossible without this system, which is itself a magnificent technology driver because the level of machine intelligence required far outstrips the state of the art (see section 3.3).
This report cannot review the entire gamut of reasons for human interest in the physical exploration of the Solar System and the Universe. Recent space research programs have stimulated large numbers of people from various scientific disciplines to join in the challenge of interplanetary exploration. Astronomers and geologists have participated since they represent the sciences traditionally most involved in the observation and classification of planetologi- cal and celestial phenomena. During the last two decades researchers from other physical sciences and the biological sciences have become interested in investigating how the laws of nature operate in the cosmos, using the techniques of radio astronomy and space exploration including direct biological samplings of other planets. Interest in the outer Solar System and deep space will likely remain high among natural scientists.
It is assumed that these reasons, coupled with the seemingly basic need of human beings to satisfy their inherent curiosity when confronted by new environments, are sufficient to motivate the economical exploration programs that advanced machine intelligence systems will make possible. Appendix ?? includes a summary of the ideas of the team's student member, Timothy Seaman, whose feelings may be representative of those of the generation of young Americans most likely to receive the first major benefits from mankind's more ambitious future ventures into space.
Although interstellar exploration was identified as the ultimate goal, detailed mission analyses are not provided. The determination of technological, economic and political feasibility for such complex, expensive, and extraordinarily long-duration undertakings must wait until advanced machine-intelligence capabilities of the type required for an extrasolar voyage have been successfully demonstrated in planetary missions conducted entirely within the Solar System. Accordingly, the major emphasis of the present study is a Titan Demonstration Mission (fig. 3.1) conceptualized to require the evolution of equipment and machine intelligence capabilities which subsequently may be applied to autonomous interstellar operations. 3.1.2 The Titan Demonstration Mission
The demonstration mission concept leads ultimately to development of a deep space - system incorporating advanced machine intelligence technology capable of condensing NASA's current three investigatory phases ? reconnaissance, exploration, and intensive study ? into a single, integrated, autonomous exploratory system. This should yield significant economies in time and resources over present methods (table 3.1). TABLE 3.1SPACE EXPLORATION: THE INTERSTELLAR GOAL AND TITAN DEMONSTRATION Goal: Evolution of capability for autonomous investigation of unknown domain. Approach: Integrate previously separate investigation steps into single mission. ? Advanced propulsion capability ? Global scale investigation by remote sensing ? Advanced sensors ? Machine intelligence for information extraction and plan follow-up ? Limited number of in situ exploration vehicles ? Autonomous hypothesis formation to classify information and develop new theories
The Space Exploration Team proposes a general-purpose robot explorer craft that could be sent to Titan, largest of Saturn's moons, as a technology demonstration experiment and major planetary mission able to utilize the knowledge and experience gained from previous NASA efforts. Titan was chosen in part because it lies far enough from Earth to preclude direct intensive study of the planet from terrestrial
