This book is one of two volumes meant to capture, to the extent practical, the sci- ti? c legacy of the Cassini-Huygens prime mission, a landmark in the history of pl- etary exploration. As the most ambitious and interdisciplinary planetary exploration mission ? own to date, it has extended our knowledge of the Saturn system to levels of detail at least an order of magnitude beyond that gained from all previous missions to Saturn. Nestled in the brilliant light of the ne w and deep understanding of the Saturn pl- etary system is the shiny nugget that is the spectacularly successful collaboration of individuals, organizations and governments in the achievement of Cassini-Huygens. In some ways the partnerships formed and lessons learned may be the most enduring legacy of Cassini-Huygens. The broad, international coalition that is Cassini- Huygens is now conducting the Cassini Equinox Mission and planning the Cassini Solstice Mission, and in a major expansion of those fruitful efforts, has extended the collaboration to the study of new ? agship missions to both Jupiter and Saturn. Such ventures have and will continue to enrich us all, and evoke a very optimistic vision of the future of international collaboration in planetary exploration.

With active geysers coating its surface with dazzlingly bright ice crystals, Saturn's large moon Enceladus is one of the most enigmatic worlds in our solar system. Underlying this activity are numerous further discoveries by the Cassini spacecraft, tantalizing us with evidence that Enceladus harbors a subsurface ocean of liquid water. Enceladus is thus newly realized as a forefront candidate among potentially habitable ocean worlds in our own solar system, although it is only one of a family of icy moons orbiting the giant ringed planet, each with its own story. As a new volume in the Space Science Series, Enceladus and the Icy Moons of Saturn brings together nearly eighty of the world's top experts writing more than twenty chapters to set the foundation for what we currently understand, while building the framework for the highest-priority questions to be addressed through ongoing spacecraft exploration. Topics include the physics and processes driving the geologic and geophysical phenomenon of icy worlds, including, but not limited to, ring-moon interactions, interior melting due to tidal heating, ejection and reaccretion of vapor and particulates, ice tectonics, and cryovolcanism. By contextualizing each topic within the profusion of puzzles beckoning from among Saturn's many dozen moons, Enceladus and the Icy Moons of Saturn synthesizes planetary processes on a broad scale to inform and propel both seasoned researchers and students toward achieving new advances in the coming decade and beyond.