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NASA Astrophysics Performance Assessment Committee, National Research Council

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A PERFORMANCE ASSESSMENT OF NASA'S ASTROPHYSICS PROGRAM

NATIONAL ACADEMIES PRESS

Contents

SUMMARY.......................................................................11 INTRODUCTION................................................................42 SUMMARY OF AANM SURVEY AND Q2C REPORT RECOMMENDATIONS.......................73 ASTROPHYSICS PROGRAM PLANS AND PROGRESS.....................................12Recent Astrophysics Achievements..............................................12Plans and Progress Toward Recommended Goals...................................204 SLOWDOWN OF PROGRESS-ANALYSIS AND APPRAISAL.................................28Internal and External Pressure on the Astrophysics Budget.....................29Mission Cost Escalation.......................................................31Science Opportunities Lost....................................................33Impact of Persistent Imbalance in the Program.................................34Organizational Instability....................................................36Community Input and Advice....................................................375 FINDINGS AND RECOMMENDATIONS................................................39APPENDIX: Acronyms............................................................45

Chapter One

Astronomy and astrophysics is in the midst of a period of unprecedented discovery, yielding new understanding of phenomena ranging from dark energy and extrasolar planets to supermassive black holes, as well as insights about the birth of the universe. Revolutionary discoveries in the field have been recognized by the awarding of four Nobel Prizes, the most recent being the 2006 Nobel Prize in Physics for the discovery, by NASA's Cosmic Background Explorer satellite, of the seed inhomogeneities in the matter density which ultimately led to all structure in the universe. Some of the breakthroughs were made by NASA missions, and some by ground-based instruments and telescopes. Always, the coordination of ground- and space-based resources has been critical to the rapid advances made in understanding the universe.

Today the field of astronomy and astrophysics is poised for more breakthroughs. Stunning opportunities for the decade of 2000-2010 were identified in the 2001 National Research Council (NRC) decadal survey Astronomy and Astrophysics in the New Millennium (AANM; National Academy Press, Washington, D.C., 2001) and expanded on in the subsequent NRC report Connecting Quarks with the Cosmos: Eleven Science Questions for the New Century (Q2C; The National Academies Press, Washington, D.C., 2003). Together the two reports laid out an ambitious program of ground- and space-based projects to turn these grand opportunities into exciting discoveries, and NASA's 2003 Astrophysics Program plan responded effectively. In particular, the 2003 plan properly addressed the stated priorities and was well optimized among mission goals, mission types, and mission sizes.

However, the implementation of the 2003 plan has been severely limited by circumstances and events both internal and external to NASA, including the Columbia disaster, mission cost overruns, smaller budgets than anticipated by the astrophysics community, and significant changes at NASA in both management and mission focus. As a result, the 2003 plan was dramatically descoped, and NASA's 2006 program plan addresses the goals of the NRC reports much less effectively than did the 2003 plan.

The sudden slowing of progress toward the exciting science goals laid out by the AANM survey and the Q2C report led to the creation of the NASA Astrophysics Performance Assessment Committee, which in this report considers how well NASA's current Astrophysics program addresses the strategies, goals, and priorities outlined in the two NRC reports; evaluates progress toward realization of those goals; and suggests mechanisms by which the scientific value of the implemented program can be optimized.

At present, NASA's Astrophysics Division does not have the resources to pursue the priorities, goals, and opportunities described in the NRC reports and has chosen to concentrate its resources on the highest-priority large and medium missions recommended by the AANM survey and those in development from the previous survey, to the detriment of the Explorer line and other small initiatives. As a result, NASA's current Astrophysics program is no longer well balanced across a desirable range of scientific areas, mission sizes, and mission-enabling activities, thus falling short of the AANM survey's specific recommendation that NASA maintain a diverse mission portfolio.

The Astrophysics Division's adopted strategy comes at a steep scientific cost, substantially reducing the prospects for future contributions to astrophysics by NASA missions. Moreover, because there will be fewer space missions, there will be fewer opportunities for coordination between space- and ground-based initiatives, and as a result the entire astronomy and astrophysics enterprise has been and will continue to be negatively impacted.

The committee recommends that NASA take a series of steps aimed at optimizing the scientific return from its Astrophysics program in the near term and laying the groundwork for continuing progress even in a restricted budget climate.

Recommendation 1: NASA should optimize the projected science return from its Astrophysics program by (a) ensuring a diversified portfolio of large and small missions that reflect the science priorities articulated in the 2001 decadal survey Astronomy and Astrophysics in the New Millennium and (b) investing in the work required to bring science missions to their full potential: e.g., technology development, data analysis, data archiving, and theory.

The most important step in implementing this recommendation is a reevaluation by the Astrophysics Division of the program's mission balance, with the goal of restoring the Explorer line to the launch rate achieved in the early part of this decade. The division should also identify structural mechanisms (e.g., firewalls, cost caps, constraints on the concentration of resources in single programs) to protect small programs and mission-enabling activities such as technology development that are critical for optimizing the science return from missions and are particularly vulnerable to cost growth in large missions, changes in accounting systems, or project budget instability.

NASA should also seek to limit cost growth in all missions by exploring ways to provide less expensive launch services (particularly for smaller missions), re-examining mission safety and assurance requirements to achieve an appropriate match with mission size, relaxing deorbit requirements for smaller spacecraft in low-cost missions, and finding improved ways to establish and maintain effective international collaborations on missions of all sizes.

Recommendation 2: NASA should consider changes in its advisory structure to shorten the path between advisory groups and relevant managers so as to maximize the relevance, utility, and timeliness of advice as well as the quality of the dialogue with advice givers. Clear communication between stakeholders and the agency is critical to a strong partnership for successfully implementing national priorities and realizing community science aspirations.

Recommendation 3: NASA should recognize that ambitious missions could require significantly more than 10 years to complete, from conception through technology readiness and launch. NASA should insist that future decadal surveys specifically include in their prioritizing deliberations those projects carried over from previous surveys that have not yet entered development (NASA Phase C/D or equivalent). To enable an accurate assessment of science success and overall life-cycle costs, NASA should, in presenting potential missions to future survey committees, also distinguish between projects that are ready for implementation and those that require significant concept design or technology investment.

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