Over the past ten years, the discovery of extrasolar planets has opened a new field of astronomy, and this area of research is rapidly growing, from both the observational and theoretical point of view. The presence of many giant exoplanets in the close vicinity of their star shows that these newly discovered planetary systems are very different from the solar system. New theoretical models are being developed in order to understand their formation scenarios, and new observational methods are being implemented to increase the sensitivity of exoplanet detections. In the present book, the authors address the question of planetary systems from all aspects. Starting from the facts (the detection of more than 300 extraterrestrial planets), they first describe the various methods used for these discoveries and propose a synthetic analysis of their global properties. They then consider the observations of young stars and circumstellar disks and address the case of the solar system as a specific example, different from the newly discovered systems. Then the study of planetary systems and of exoplanets is presented from a more theoretical point of view. The book ends with an outlook to future astronomical projects, and a description of the search for life on exoplanets. This book addresses students and researchers who wish to better understand this newly expanding field of research.

Over the past ten years, the discovery of extrasolar planets has opened a new field of astronomy, and this area of research is rapidly growing, from both the observational and theoretical point of view. The presence of many giant exoplanets in the close vicinity of their star shows that these newly discovered planetary systems are very different from the solar system. New theoretical models are being developed in order to understand their formation scenarios, and new observational methods are being implemented to increase the sensitivity of exoplanet detections. In the present book, the authors address the question of planetary systems from all aspects. Starting from the facts (the detection of more than 300 extraterrestrial planets), they first describe the various methods used for these discoveries and propose a synthetic analysis of their global properties. They then consider the observations of young stars and circumstellar disks and address the case of the solar system as a specific example, different from the newly discovered systems. Then the study of planetary systems and of exoplanets is presented from a more theoretical point of view. The book ends with an outlook to future astronomical projects, and a description of the search for life on exoplanets. This book addresses students and researchers who wish to better understand this newly expanding field of research.

The detection and exploration of extrasolar planets is one of the most exciting and fast moving areas of astronomical research at the present time. With over forty research programmes ongoing, and just as many planned, the search for these new worlds has become the main objective for a new generation of giant ground-based telescopes as well as many future space missions. Experimental methods and observational techniques are pushing existing instruments to their limits. The most exciting possibility offered by this research is the discovery of Earth-like extrasolar planets, with a mass comparable to that of Earth, located at the right distance from its star to host liquid water - in other words, a place where life could evolve. The authors tackle this challenging field of research by first looking at early searches for extrasolar planets, the very first discoveries and the observational techniques involved. They, then examine the very wide range of extrasolar planets that have been discovered during the past ten years and look at what we can learn about such planets by studying the bodies in our own solar system.The formation of planetary systems, the way in which such systems may evolve and the final systems of planets that result are then discussed. Finally, Drs Casoli and Encrenaz examine the possibilities for life on extrasolar planets, again using our own solar system as a model, and look to the plans for future extrasolar planet searches. A number of Appendices summarise the extrasolar planet discoveries to date.