A Unified Two-Decade Strategy for Solar-System Habitability, Biosignatures, and Exoplanet Exploration

The Search for Life in the Coming Decades

Taking the 2015 Astrobiology Strategy (NASA 2015) as its starting point and building on that foundation, Chapters 2, 3, 4, and 5 of this report emphasized additional insights from recent advances in the search for signs of life—intellectual (e.g., conceptual insights and frameworks, modeling), empirical (e.g., key discoveries and observations, technology development, and novel technologies), and programmatic. Building on those updates, in this chapter, the committee identifies the most promising key research goals and questions in the field in which progress is likely in the next 20 years, and discusses pathways by which of the key goals can be addressed by U.S. and international space missions and ground telescopes in operation or in development.