that permeate space. The opportunities for the future fill us with awe, enrich our culture, and frame our view of the human condition.
This report is the result of the National Research Council’s (NRC’s) survey of astronomy and astrophysics for the decade of the 2010s—Astro2010. The survey covers what has been learned, what could be learned, and what it will take to sustain the current revolution in understanding. As requested, the report outlines a plan to realize the scientific promise of the decade to come. The recommended major new elements must be combined with ongoing support for and augmentation of the foundational core of the federally supported research program to ensure a balanced program in astronomy and astrophysics that optimizes overall scientific return.
Below and in subsequent chapters of this report the Committee for a Decadal Survey of Astronomy and Astrophysics presents a compelling science program (Chapter 2), outlines the relationship of the federal program to the larger astronomy and astrophysics enterprise (Chapters 3 and 4), discusses workforce development and other core activities (Chapters 5 and 6), and describes in detail the integrated program it recommends for the decade ahead (Chapter 7). The process that was followed in carrying out Astro2010 is recounted in this report’s preface and reviewed again in Chapter 7.
The exciting program of activities proposed here will help to advance understanding of how the first galaxies formed and started to shine. It will direct the discovery of the closest habitable planets beyond our solar system. It will use astronomical measurements to try to unravel the mysteries of gravity and will probe fundamental physics beyond the reach of Earth-based experiments. The committee found that the way to optimize the science return for the decade 2012-2021 within the anticipated resources was to focus on these three science objectives while also considering the discovery potential of a much broader research program. To achieve these objectives, a complementary effort of space-based, ground-based, and foundational, core research is required.
We have learned much in recent years about the history of the universe, from the big bang to the present day. A great mystery now confronts us: When and how did the first galaxies form out of cold clumps of hydrogen gas and start to shine—when was our “cosmic dawn”? Observations and calculations suggest that this phenomenon occurred when the universe was roughly half a billion years old, when light from the first stars was able to ionize the hydrogen gas in the universe