ABSTRACT
This chapter reviews current knowledge on icy-covered ocean worlds in the solar system—satellites of the giant planets and at least one Kuiper Belt object—and current thinking on their prospects for supporting life. These worlds contain abundant liquid water, the first prerequisite for life, as it exists on Earth. From the handful of additional available constraints obtained by spacecraft missions, some of these worlds also appear to provide the chemical conditions needed to sustain life. Planned spacecraft missions will begin to look for signs of habitability and extant life in some of these icy ocean worlds, and missions to follow in the ensuing decades may have the chance to sample living organisms directly.
