Pathways to Discovery in Astronomy and Astrophysics for the 2020s

We live in a time of extraordinary discovery and progress in astronomy and astrophysics. The next decade will transform our understanding of the universe and humanity's place in it. Every decade the U.S. agencies that provide primary federal funding for astronomy and astrophysics request a survey to assess the status of, and opportunities for the Nation's efforts to forward our understanding of the cosmos. Pathways to Discovery in Astronomy and Astrophysics for the 2020s identifies the most compelling science goals and presents an ambitious program of ground- and space-based activities for future investment in the next decade and beyond. The decadal survey identifies three important science themes for the next decade aimed at investigating Earth-like extrasolar planets, the most energetic processes in the universe, and the evolution of galaxies. The Astro2020 report also recommends critical near-term actions to support the foundations of the profession as well as the technologies and tools needed to carry out the science. Table of Contents Front Matter Summary 1 Pathways to Discovery: From Foundations to Frontiers 2 A New Cosmic Perspective 3 The Profession and Its Societal Impacts: Gateways to Science, Pathways to Diversity, Equity, and Sustainability 4 Optimizing the Science: Foundations 5 Evaluating and Balancing the Operational Portfolio 6 Technology Foundations and Small- and Medium-Scale Sustaining Programs 7 Realizing the Opportunities: Medium- and Large-Scale Programs Appendixes Appendix A: Statement of Task, Additional Guidance, and Panel Descriptions Appendix B: Report of the Panel on Compact Objects and Energetic Phenomena Appendix C: Report of the Panel on Cosmology Appendix D: Report of the Panel on Galaxies Appendix E: Report of the Panel on Exoplanets, Astrobiology, and the Solar System Appendix F: Report of the Panel on the Interstellar Medium and Star and Planet Formation Appendix G: Report of the Panel on Stars, the Sun, and Stellar Populations Appendix H: Report of the Panel on an Enabling Foundation for Research Appendix I: Report of the Panel on Electromagnetic Observations from Space 1 Appendix J: Report of the Panel on Electromagnetic Observations from Space 2 Appendix K: Report of the Panel on Optical and Infrared Observations from the Ground Appendix L: Report of the Panel on Particle Astrophysics and Gravitation Appendix M: Report of the Panel on Radio, Millimeter, and Submillimeter Observations from the Ground Appendix N: Report of the Panel on State of the Profession and Societal Impacts Appendix O: Independent Technical, Risk, and Cost Evaluation Appendix P: Acronyms and Abbreviations Appendix Q: Committee and Panel Biographical Information