NASA evolution of exploration architectures

A series of charts and diagrams is used to provide a detailed overview of the evolution of NASA space exploration architectures. The pre-Apollo programs including the Werner von Braun feasibility study are discussed and the evolution of the Apollo program itself is treated in detail. The post-Apollo era is reviewed and attention is given to the resurgence of strategic planning exemplified by both ad hoc and formal efforts at planning. Results of NASA's study of the main elements of the Space Exploration Initiative which examined technical scenarios, science opportunities, required technologies, international considerations, institutional strengths and needs, and resource estimates are presented. The 90-day study concludes that, among other things, major investments in challenging technologies are required, the scientific opportunities provided by the program are considerable, current launch capabilities are inadequate, and Space Station Freedom is essential.