[These books provide] a discursive and authoritative view of the latest ideas and information on the history, structure and evolution of Halley's Comet, as observed by international organizations in a lively and informative manner, highlighting areas of agreement, theoretical speculation and controversy.

A look at the role comets may have played in the origins and evolution of life, particularly in light of recent investigations of Halleys comet, new insights into organic synthesis in meteorites and comets, and new results of numerical simulations of cometary orbits and impacts on Earth. This is a comprehensive review of current research, accessible to graduate students and others new to the field. Each chapter was prepared by an expert in the field, and carefully revised by the editors for uniformity in style and presentation.

Since several decades, comets have been considered as key witnesses of solar system formation. Their nature has been explored using the modern arsenal of Earth- and space-based observations, and they hold a central place as dynamical arbiters of the planetary system in the new paradigm of solar system evolution known as the Nice Model. Thus, they have the potential to test the various ideas, using the detailed data recently gathered by the ESA/Rosetta mission. This requires an understanding of their origin and evolution, which form the subject of the present book. All the relevant issues are covered, describing both the background and the current frontiers of research.

As this excellent book demonstrates, the study of comets has now reached the fas cinating stage where we understand comets in general simple tenns while, at the same time, we are uncertain about practically all the details of cometary nature, structure, processes, and origin. In every aspect, even including dynamics, a choice among several or many competing theories is made impossible simply by the lack of detailed knowledge. The space missions, snapshot studies of two comets, partic ularly the one that immortalizes the name of Sir Edmund Halley, have produced a huge mass of valuable new infonnation and a number of surprises. Nonetheless, we face the tantalizing realization that we have obtained only a fleeting glance at two of perhaps a hundred billion (lOll) or more comets with possibly differing natures, origins, and physical histories. To my personal satisfaction, comets seem to have discrete nuclei made up of dirty snowballs, as I concluded four decades ago, but perhaps they are more like frozen rubbish piles.

Comet nuclei are the most primitive bodies in the solar system. They have been created far away from the early Sun and it is supposed that their material has been altered the least since their formation. This volume presents the results of a scientific workshop on comet nuclei and is written by experts working on interstellar clouds, star-forming regions, the solar nebula, and comets. The articles formulate the current understanding and interconnectivity of the various source regions of comet nuclei and their associated compositions and orbital characteristics. This includes a discussion on the transport of materials into the Kuiper belt and Oort cloud regions of the solar system. The distinction between direct measurements of cometary material properties and properties derived from indirect means are emphasized with the aim to guide future investigations. This book serves as a guide for researchers and graduate students working in the field of planetology and solar system exploration. It should also help to influence the planning of scientific strategies for the encounter of the Rosetta spacecraft with Comet Churyumov-Gerasimenko.

This book provides a comprehensive overview of our current knowledge of comets. It presents a fascinating survey of the study of comets throughout history, from antiquity to the present day, and includes the most recent discoveries on the exceptional comets Hale-Bopp and Hyakutake. The authors discuss the role of comets in the formation of our Solar System and describe the links between comets, asteroids and the recently discovered Kuiper-belt objects. The book also includes new insights into the composition and nature of cometary nuclei, with results from the most up-to-date observation techniques. Written in a clear and lively style, and beautifully illustrated, this book will appeal to anyone interested in comets and astronomy, professionals and amateurs alike. It will be of particular interest to students and researchers in astronomy, astrophysics and planetary science, as well as general readers with a good background in physics.