Effective science, clearly a mandate for the National Aeronautics and Space Administration (NASA), involves asking significant questions about the physical and biological world and seeking definitive answers. Its product is new knowledge that has value to the nation. NASA's flight projects are highly visible and usually the most costly elements of this process, but they are only a part of the science enterprise. Flight projects are founded on research that defines clear scientific goals and questions, designs missions to address those questions, and develops the required technologies to accomplish the missions. This research is funded primarily by NASA's research and analysis (R&A) programs. Data from flight projects are transformed into knowledge through analysis and synthesis-research that is funded both by R&A and by the data analysis (DA) portion of mission operations and data analysis (MO&DA) programs. R&A and DA programs are the subject of this report and are grouped for convenience under the heading of research and data analysis (R&DA).

The Research and Analysis (R&A) program managed by NASA's Planetary Science Division (PSD), supports a broad range of planetary science activities, including the analysis of data from past and current spacecraft; laboratory research; theoretical, modeling, and computational studies; geological and astrobiological fieldwork in planetary analog environments on Earth; geological mapping of planetary bodies; analysis of data from Earth- and space-based telescopes; and development of flight instruments and technology needed for future planetary science missions. The primary role of the PSD R&A program is to address NASA's strategic objective for planetary science and PSD's science goals. Recently, PSD reorganized the R&A program to provide better alignment with the strategic goals for planetary sciences. The major changes in the R&A program involved consolidating a number of prior program elements, many of which were organized by subdiscipline, into a smaller number of thematic core research program elements. Despite numerous efforts by PSD to communicate the rationale for the reorganization and articulate clearly the new processes, there has been significant resistance from the planetary science community and concerns in some sectors regarding the major realignment of funding priorities. Review of NASA's Planetary Science Division's Restructured Research and Analysis Programs examines the new R&A program and determines if it appropriately aligns with the agency's strategic goals, supports existing flight programs, and enables future missions. This report explores whether any specific research areas or subdisciplinary groups that are critical to NASA's strategic objectives for planetary science and PSD's science goals are not supported appropriately in the current program or have been inadvertently disenfranchised through the reorganization.

NASA's space and Earth science program is composed of two principal components: spaceflight projects and mission-enabling activities. Most of the budget of NASA's Science Mission Directorate (SMD) is applied to spaceflight missions, but NASA identifies nearly one quarter of the SMD budget as "mission enabling." The principal mission-enabling activities, which traditionally encompass much of NASA's research and analysis (R&A) programs, include support for basic research, theory, modeling, and data analysis; suborbital payloads and flights and complementary ground-based programs; advanced technology development; and advanced mission and instrumentation concept studies. While the R&A program is essential to the development and support of NASA's diverse set of space and Earth science missions, defining and articulating an appropriate scale for mission-enabling activities have posed a challenge throughout NASA's history. This volume identifies the appropriate roles for mission-enabling activities and metrics for assessing their effectiveness. Furthermore, the book evaluates how, from a strategic perspective, decisions should be made about balance between mission-related and mission-enabling elements of the overall program as well as balance between various elements within the mission-enabling component. Collectively, these efforts will help SMD to make a good program even better.

Assessment of Mission Size Trade-offs for NASA's Earth and Space Science Missions addresses fundamental issues of mission architecture in the nation's scientific space program and responds to the FY99 Senate conference report, which requested that NASA commission a study to assess the strengths and weaknesses of small, medium, and large missions. This report evaluates the general strengths and weaknesses of small, medium, and large missions in terms of their potential scientific productivity, responsiveness to evolving opportunities, ability to take advantage of technological progress, and other factors that may be identified during the study; identifies which elements of the SSB and NASA science strategies will require medium or large missions to accomplish high-priority science objectives; and recommends general principles or criteria for evaluating the mix of mission sizes in Earth and space science programs. Assessment of Mission Size Trade-offs for NASA's Earth and Space Science Missions considers not only scientific, technological, and cost trade-offs, but also institutional and structural issues pertaining to the vigor of the research community, government-industry university partnerships, graduate student training, and the like.