Christopher F. Chyba – författare

What role should nuclear weapons play in today's world? How can the United States promote international security while safeguarding its own interests? U.S. Nuclear Weapons Policy informs this debate with an analysis of current nuclear weapons policies and strategies, including those for deterring, preventing, or preempting nuclear attack; preventing further proliferation, to nations and terrorists; modifying weapons designs; and revising the U.S. nuclear posture. Presidents Bush and Clinton made major changes in U.S. policy after the Cold War, and George W. Bush's administration made further, more radical changes after 9/11. Leaked portions of 2001's Nuclear Posture Review, for example, described more aggressive possible uses for nuclear weapons. This important volume examines the significance of such changes and suggests a way forward for U.S. policy, emphasizing stronger security of nuclear weapons and materials, international compliance with nonproliferation obligations, attention to the demand side of proliferation, and reduced reliance on nuclear weapons in U.S. foreign policy.

Nine years after the publication of Comets and the Origin and Evolution of Life, one of the pioneering books in Astrobiology, this second edition revisits the role comets may have played in the origins and evolution of life. Recent analyses of Antarctic micrometeorites and ancient rocks in Australia and South Africa, the continuing progress in discovering complex organic macromolecules in comets, protostars and interstellar clouds, new insights into organic synthesis in comets, and numerical simulations of comet impacts on the Earth and other members of the solar system yield a spectacular wealth of new results.This second edition is thus actually a new book. As the first edition it is intended as a comprehensive review of current research, accessible to graduate students and others new to the field. Each chapter was prepared by experts to give an overview of an aspect of the field, and carefully revised by the editors for uniformity in style and presentation.