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Small Bodies in Planetary Systems.Pdf Lecture Notes in Physics Founding Editors: W. Beiglbock,¨ J. Ehlers, K. Hepp, H. Weidenmuller¨ Editorial Board R. Beig, Vienna, Austria W. Beiglbock,¨ Heidelberg, Germany W. Domcke, Garching, Germany B.-G. Englert, Singapore U. Frisch, Nice, France F. Guinea, Madrid, Spain P. Hanggi,¨ Augsburg, Germany G. Hasinger, Garching, Germany W. Hillebrandt, Garching, Germany R. L. Jaffe, Cambridge, MA, USA W. Janke, Leipzig, Germany H. v. Lohneysen,¨ Karlsruhe, Germany M. Mangano, Geneva, Switzerland J.-M. Raimond, Paris, France D. Sornette, Zurich, Switzerland S. Theisen, Potsdam, Germany D. Vollhardt, Augsburg, Germany W. Weise, Garching, Germany J. Zittartz, Koln,¨ Germany The Lecture Notes in Physics The series Lecture Notes in Physics (LNP), founded in 1969, reports new developments in physics research and teaching – quickly and informally, but with a high quality and the explicit aim to summarize and communicate current knowledge in an accessible way. Books published in this series are conceived as bridging material between advanced grad- uate textbooks and the forefront of research and to serve three purposes: • to be a compact and modern up-to-date source of reference on a well-defined topic • to serve as an accessible introduction to the field to postgraduate students and nonspecialist researchers from related areas • to be a source of advanced teaching material for specialized seminars, courses and schools Both monographs and multi-author volumes will be considered for publication. Edited volumes should, however, consist of a very limited number of contributions only. Pro- ceedings will not be considered for LNP. Volumes published in LNP are disseminated both in print and in electronic formats, the electronic archive being available at springerlink.com. The series content is indexed, ab- stracted and referenced by many abstracting and information services, bibliographic net- works, subscription agencies, library networks, and consortia. Proposals should be sent to a member of the Editorial Board, or directly to the managing editor at Springer: Christian Caron Springer Heidelberg Physics Editorial Department I Tiergartenstrasse 17 69121 Heidelberg / Germany [email protected] I. Mann A.M. Nakamura T. Mukai (Eds.) Small Bodies in Planetary Systems 123 Ingrid Mann Akiko M. Nakamura Kobe University Kobe University Dept. Earth & Planetary Sciences Dept. Earth & Planetary Sciences Rokkodai-cho Kobe Rokkodai-cho Kobe Nada-ku 657-8501 Nada-ku 657-8501 Japan Japan [email protected] Tadashi Mukai Kobe University Dept. Earth & Planetary Sciences Rokkodai-cho Kobe Nada-ku 657-8501 Japan Mann, I. et al. (Eds.), Small Bodies in Planetary Systems, Lect. Notes Phys. 758 (Springer, Berlin Heidelberg 2009), DOI 10.1007/978-3-540-76935-4 ISBN: 978-3-540-76934-7 e-ISBN: 978-3-540-76935-4 DOI 10.1007/978-3-540-76935-4 Lecture Notes in Physics ISSN: 0075-8450 Library of Congress Control Number: 2008929548 c Springer-Verlag Berlin Heidelberg 2009 This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilm or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Springer. Violations are liable to prosecution under the German Copyright Law. The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Cover design: eStudio Calamar S.L., F. Steinen-Broo, Pau/Girona, Spain Printed on acid-free paper 987654321 springer.com Preface The small bodies in planetary systems are indicative of the material evolu- tion, the dynamical evolution, and the presence of planets in a system. Recent astronomical research, space research, laboratory research, and numerical sim- ulations brought a wealth of new and exciting findings on extra-solar planetary systems and on asteroids, comets, meteoroids, dust, and trans-Neptunian ob- jects in the solar system. Progress in astronomical instrumentation led to the discovery and investigation of small bodies in the outer solar system and to observations of cosmic dust in debris disks of extra-solar planetary systems. Space research allowed for close studies of some of the small solar system bodies from spacecraft. This lecture series is intended as an introduction to the latest research results and to the key issues of future research. The chap- ters are mainly based on lectures given during a recent research school and on research activities within the 21st Century COE Program “Origin and Evolution of Planetary Systems” at Kobe University, Japan. In Chap. 1, Taku Takeuchi discusses the evolution of gas and dust from protoplanetary disks to planetary disks. Using a simple model, he studies vis- cous evolution and photoevaporation as possible mechanisms of gas dispersal. He further considers how the dust grows into planetesimals. Motion of dust particles induced by gas drag is described, and then using a simple analytic model, the dust growth timescale is discussed. Chap. 2 by Mark Wyatt covers the interpretation of observations of small bodies in extrasolar planetary systems. While observations of debris disks trace the distribution of dust in these systems, they can be used to infer the distribution of larger bodies: planetesimals and planets. The chapter describes a theory for the dynamics of dust–planetesimal–planet interactions. Such a theory is essential for a successful interpretation of the observations, and is equally applicable to the study of dust originating in the asteroid and Kuiper belts in the solar system. The collisional disruption of small bodies is a fundamental process in the formation and evolution of planetary systems. In Chap. 3, Akiko Naka- mura and Patrick Michel describe the current knowledge on collision VI Preface processes of asteroids and relevant laboratory studies. Related recent findings from the Hayabusa mission to the small asteroid 25143 Itokawa are shortly described. Subsequently, Patrick Michel presents in Chap. 4 the different disruption mechanisms that can affect the physical properties of small bodies in planetary systems over their history. Our current but still very poor understanding of the concept of material strength of those bodies and its role in the action of those mechanisms are also described. In Chap. 5 Shinsuke Abe discusses meteor observations in connection to properties of the meteoroid parent bodies. Meteors are phenomena that re- sult from interaction of meteoroids entering from interplanetary space with the Earth’s upper atmosphere. The derived meteoroid characteristics bear po- tential information to investigate their parent bodies, which are in majority comets and asteroids. Except for the meteor observations, the few cases of in-situ detections in space, and the limited studies of cosmic samples in terrestrial laboratories, our information concerning small bodies in planetary systems are based on astronomical observations, especially on the observations of cosmic dust. In Chap. 6, Aigen Li presents the theoretical basis for describing the optical properties of dust and the dust interaction with electromagnetic radiation. The physical processes of the dust in planetary debris disks are discussed in Chap. 7 by Ingrid Mann. Planetary debris disks are exposed to the brightness of the central star, stellar wind, and energetic particles originating from the system as well as galactic cosmic ray particles. Both stellar radiation and stel- lar wind give rise to a Poynting–Robertson effect, which limits the lifetime of the dust particles that are in bound orbit about the star (migration-dominated disks). In debris disks with high dust content lifetimes due to mutual collisions are even shorter (collision-dominated disks). Dust collisions are a potential source of second-generation gas in planetary debris disks. The chapter also touches on the role of non-thermal alteration for dust material evolution. In Chap. 8, Masateru Ishiguro and Munetaka Ueno describe recent devel- opments in observations of interplanetary dust particles. These developments are largely due to the introduction of cooled charge coupled device (CCD) de- tectors and two-dimensional infrared array detectors used with infrared space telescopes. The new observational data show not only the global structure of the interplanetary dust cloud, e.g., its plane of symmetry, but also faint structures, asteroidal dust bands, and cometary dust trails, seen as brightness enhancements of a few percent above that of the smooth component. Spectro- graphic observations provide some knowledge about the dynamics and com- position of these local components. The observations reveal the connections between interplanetary dust particles and their parent bodies. The chapter ends by describing ongoing and future projects related to the observational study of interplanetary dust. Preface VII The past 15 years have seen a renaissance in the study of the outer solar system with the discovery of the Kuiper belt and the unveiling of previ- ously unexpected connections between distinct sub-populations of small bod- ies throughout the system.
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