must be, a major consideration in design, development, testing, launch, spaceflight use, and ultimate disposal. That is, from beginning to end. Stringent safety requirements and rigorous safety reviews have been imposed upon every US nuclear space power system development/flight program. Although somewhat rigid in its formalism, the process has served us well and has also stimulated two very positive, interactive safety functions: (1) building safety into the design from the outset, and (2) assuring that safety is adequately characterized and reflected in the design, through recurring assessments. To carry out these functions effectively, internal and external accident situations, that can occur over the system's full life cycle, must continue to be considered. Such an inter-active, life-cycle approach to nuclear space power system safety is valuable and desirable. It provokes design foresight, provides focus for safety/risk assessments, and establishes a useful feedback mechanism to the design process. These positive attributes are now being embraced in the development of US nuclear space power systems; the process which has ‘given life' to them should be fostered. To help set the stage for discussion, an historical overview of the US nuclear space power system safety, safety review/evaluation, and launch approval processes is first provided. Within this overview, specific safety design and assessment techniques are highlighted. The emergence, within the US, of a more interactive safety process during system design and development is then discussed; its effectiveness is addressed via examples from the SP-100 Space Reactor Power System Development Program. Lastly, those safety processes and issues considered essential to the protection of the nuclear space power system option are identified and discussed. The conclusion reached is that nuclear space power system safety, from beginning to end, is manageable and can be adequately provided. Furthermore, with timely, effective integration and continued application of sound safety principles and processes, the viability of the nuclear power option for near-term and future space missions can be demonstrated—convincingly. (Paper number IAF-ICOSP89-11-1.) REFERENCES [1] Bennett, G.L. & Buden, D. (1983) Use of nuclear reactors in space, The Nuclear Engineer, 24, 4, July/August, pp. 108-117. [2] Bennett, G.L. (1981) Overview of the US flight safety process for space nuclear power, Nuclear Safety, 22, 4, July/August, pp. 423-434. 11-5. Safety and Environmental Analyses of Space Nuclear Power Systems D. G. McConnell USA. It is vital to future US space leadership that the environmental analyses of space nuclear systems not block their development as has become the case with US earth-based nuclear power systems. This paper presents a case study of the Galileo environmental analysis and highlights lessons learned as guidelines for future space programs. Nuclear power subsystems have enabled the achievement of some of the USA's most successful space missions: the Galileo Lunar Surface Experiment Packages (ALSEPs), the Viking Launchers on Mars, Pioneers 10 and 11—now actually entering interstellar space and still returning data—and Voyagers 1 and 2 which revolutionized our knowledge of the outer planets. Isotope power systems (RTGs) are, in fact, the only available power systems which can provide sufficient power within limits of weight, volume, and reliability for extended mission to the outer planets. As this is the area of US pre-eminence, future missions should not be needlessly precluded. Space reactors are under study for such existing missions as the Lunar Base and Mars Rover Sample Return (MRSR). Human outposts on the Moon and Mars will almost certainly need to consider nuclear reactor power systems. Now it is both prudent and sound to consider the safety and environmental issues of
RkJQdWJsaXNoZXIy MTU5NjU0Mg==