The annual meeting of the Astronomische Gesellschaft in Cologne, June 1988, featured extensive reviews of the chemical processes relevant to astrophysics. The twelve contributions to this book, written by experts from the US, UK, France, Belgium, Switzerland and Germany, deal in depth with the chemistry of comets and meteorites, of stars and their shells, of the interstellar medium and galaxies. A comprehensive review of nucleosynthesis and two reports on observations round off an up-to-date presentation of cosmic chemistry.

This book is devoted to the quantitative physical modeling of subduction and subduction-related processes. It presents a coherent description of the modeling method (including similarity criteria, and a novel applied experimental technique), results from model experiments, theoretical analysis of results on the basis of continuum mechanics, and their geodynamic interpretation. Subduction is modeled in general as well as applied to particular regions using both 2-D and 3-D approaches, with both slab-push and slab-pull driving forces. The modeling covers all stages from subduction initiation to death', different regimes of subduction producing back arc extension and compression, blocking of subduction and jumps of subduction zone, arc-continent collision and continental subduction. This work is for geologists and geophysicists interested in geodynamics of the convergent plate boundaries and in mechanics of the lithosphere.

Major structural features are used in this study to reconstruct the links which existed between North America, Europe and Africa before the opening of the North Atlantic Ocean. The synthesis of geophysical and geochemical data as well as geological observations allows the recognition of the original geometry of the Grenvillian, Cadomian, Caledonian, Ligerian-Acadian and Hercynian foldbelts and the identification of ancient plate sutures. The reader will find a wealth of information based not only on the English but also on the French and Spanish literature, thus opening less known results to the international community.

Experts report the state of the art in the study of global climate change using remote sensing techniques. Topics covered include the principles of remote sensing, the management of data, data requirements in climatology, the principles of modelling, the input of data into models, and the application of remote sensing to the atmosphere, ice and snow, seas and land.
The book is highly topical given the current great public and scientific awareness of possible man-made changes to the climate. It is essential reading for anyone new to the field, and invaluable as a reference work to those already working in it.

This book presents the results of the Third International Symposium on Observation of the Continental Crust through Drilling held in Mora and Orsa, Sweden, September 7 - 10, 1987. Volume 2 reviews new and general information on geology, geophysics, rock mechanics, geochemistry, drilling techniques and drilling problems in very deep holes of the FRG, USA and the Soviet Union. The proceedings are invaluable for earth scientists as well as for exploiters of geoenergy and other natural resources in the crust. Volume 1 summarizes the results of the Deep Gas Project in the Siljan impact structure, Sweden, including papers dealing with general aspects of astroblemes. It is of interest to all researchers working in the drilling industry and those interested in the problem of "deep gas."

The present work is not exactly a "course," but rather is presented as a monograph in which the author has set forth what are, for the most part, his own results; this is particularly true of Chaps. 7-13. Many of the problems dealt with herein have, since the school year 1975-76, been the subject of a series of graduate lectures at the "Universire des Sciences et Techniques de Lille I" for students preparing for the "Diplome d'Etudes Ap profondies de Mecanique (option fluides)." The writing of this book was thus strongly influenced by the author's own conception of meteorology as a fluid mechanics discipline which is in a privi leged area for the application of singular perturbation techniques. It goes without saying that the modeling of atmospheric flows is a vast and complex problem which is presently the focal point of many research projects. The enonnity of the topic explains why many important questions have not been taken up in this work, even among those which are closely related to the subject treated herein. Nonetheless, the author thought it worthwhile for the development of future research on the modeling of atmospheric flows (from the viewpoint of theoretical fluid mechanics) to bring forth a book specifying the problems which have already been resolved in this field and those which are, as yet, unsolved."

This volume contains the proceedings of a NATO Advanced study Institute held at Geilo, Norway between 2 - 12 april 1991. This institute was the eleventh in a series held biannually at Geilo on the subject of phase transitions. It was intended to capture the latest ideas on selforgan ized patterns and criticality. The Institute brought together many lecturers, students and active re searchers in the field from a wide range of NATO and non-NATO countries. The main financial support came from the NATO scientific Affairs Divi sion, but additional support was obtained from the Norwegian Research Council for Science and the Humanities (NAVF) and Institutt for energi teknikk. The organizers would like to thank all these contributors for their help in promoting an exciting and rewarding meeting, and in doing so are confident that they echo the appreciation of all the parti cipants. In cooperative, equilibrium systems, physical states are described by spatio-temporal correlation functions. The intimate connection between space and time correlations is especially apparent at the critical point, the second order phase transition, where the spatial range and the decay time of the correlation function both become infinite. The salient features of critical phenomena and the history of the devel opment of this field of science are treated in the first chapter of this book.

These Proceedings are published to give a full account of the Fifth International Conference on Atmospheric Electricity held in September 1974 in Garmisch-Partenkirchen in the Bavarian Alps in Germany. Traditionally, the Proceedings of these Conferences have served as reference books updating the textbooks and monographs on Atmospheric Electricity. As treated by these Conferences, Atmos pheric Electricity covers all aspects of this science, including the processes and problems which reach out into the Earth's environment as well as analogous processes on other planets and on the Moon. A history of these Conferences, an account of their purpose, and an outline of the scope and the preparation is to be found at the end of these Proceedings. There, also the Business Meetings of the involved organizations are mentioned. The Proceedings closely follow the original program and are accordingly organized into "Sessions." The papers printed in each "Session" in this book are the ones which were accepted for the sessions of the Conference with the same numbers and titles. Only the two "Special Sessions" have been given different numbers in the Proceedings, i.e. 2a and 10. In principle, all papers which were accepted by the Executive Panel either for full oral presentation or for printing in the Proceedings only, have in fact been included in these Proceedings, whether they were presented or not. In the latter case, a special note is made to explain the absence of a discussion."

The earth is seen as a dynamic body undergoing convection that is driven by its internal heat. The elucidation of the nature and evolution of the earth's lithosphere, that has provided all minerals and energy resources and the space in which we live is one of the principal motives behind the International Program "Dynamics and Evolution of the Lithosphere". A full understanding of the lithosphere requires further research especially on the continents and their margins: while the oceanic lithosphere cools and subsides as it flows away from the zone of upwelling, the continents, because of their different composition, remain buoyant in the mantle and survive over major portions of the earth's history. In trying to produce full confirmation of the validity of sea floor spreading and lithosphere subduction, Central Europe became more and more a crucial case. The deformation of continental plates is, however, more complex than that of the ocean-floor pattern. No discrete boundary exists between both the African and Eurasian plates. A number of unanswered questions arise e.g. whether African crust has overridden Europe, or European lithosphere collided in the ranges of Atlas of Algeria. The work of German, French and Suiss geologists accomplished much during this century. Central Europe has come to serve as a test site for the refinement of plate tectonics. A new understanding of the crustal dynamics of Central Europe was born with the aim of explaining its structural evolution.

In 1998 Armenia was commemorating the tenth anniversary of the catastrophic Spitak earthquake. The Second International Conference on "Earthquake Hazard and Seismic Risk Reduction" sponsored by the Government of the Republic of Armenia and United Nation's International Decade for Natural Disaster Reduction (UN/IDNDR) was held in dedication to that event between 14-21 September (later referred to as Yerevan Conference). The Yerevan Conference has been organized by the National Survey for Seismic Protection (NSSP) of the Republic of Armenia. All level's decision-makers (from the ministers to the local authorities), politicians, scientists, leaders of the executive and legislative powers, psychologists, leading businessmen, representatives from the private sector and the media as well as from the International Organizations have been invited by the Armenian NSSP to take part in joint discussion of the Seismic Risk Reduction Problem for the first time in the history of such forums. Armenian NSSP's such initiative has been triggered by the experience of the Spitak earthquake and other disasters. They showed that it will be possible to reduce the risks, posed by the natural disaster, only through the common efforts of all the community in co-operation with the International institutions.

Progress towards an understanding of the dynamics and interactions of galaxies has been spurred on more than ever by a wealth of new observations and numerical experiments. The Heidelberg Conference 1989, the papers of which are collected in this volume, was extremely successful in presenting a synoptic view of the field in all its aspects: galaxy interactions in the early universe and in recent times, interactions of our galaxy and its neighbours, dynamical problems of elliptical and disk galaxies, groups and clusters, starburst and nuclear activity triggered by interactions, merger scenarios, and numerical experiments. Researchers and graduate students, specialists or not, will find here a complete overview of a rapidly growing field of astronomy.

During the revolution in earth science that has taken place in recent years, studies of the North Atlantic ocean floor and of Iceland have played an increasingly significant role. Icelandic geoscientists have followed, and taken part in, these studies with a keen interest; one of the first tasks of the Geoscience Society of Iceland was to organize an Icelandic symposium on "Iceland and Mid-Ocean Ridges" in 1967. At the suggestion of Dr. G. Pfuason, the Society and various local research institutions formed in 1972 an Organizing Committee for an international meeting on earth science. It was decided that it should be devoted to examining the various expressions of geo namical forces in the North Atlantic area, in particular at the ocean ridges passing through Iceland. Apart from the scientific content of such a meeting, the organizers also felt it was highly important for scientists from both sides of the Atlantic to meet in Iceland, to become acquainted with recent progress in earth science research there and to coordinate their future research projects in the area. The meeting was held in Reykj avik 1 - 7 July, 1974, and was followed by field trips in Iceland. Generous financial support from the NATO Scient'ific Affairs Division, the Inter-Union Com mission on Geodynamics, and many other sources, is gratefully acknowledged."

The drilling site of the KTB is located on the western margin of the Bohemian Massif, a few kilometers south of the structurally important Saxothur ing ian/Moldanubian boundary of the central European Hercynian orogene and several kilometers east of one of the most important Permian-Mesozoic strike-slip zones of central Europe, the Franconian line. The borehole will be drilled in the Moldanubian segment (Fig. 1). o -::: --. . . . . . . . -. . -. D Il1O, Fig. l: Geological map of the Central Europe Variscides and location of borehole From geographical and political points of view, the drill site is located in northern Bavaria in the Oberpfalz province near the towns of Windischeschenbach and Erbendorf about 40 km southeast of Bayreuth. TARGETS AND RESEARCH TOPICS 'The Continental Deep Drilling program of the Federal Republic of Germany (KTB) is a project of basic geoscientific research. The program and goals of this project have been set by a board of the Senate Commission on Geosciences of the German Research Foundation (DFG). The technical concept of the drilling, sampling, coring and logging programs corresponds to these goals. The upper limit of the budget of 450 million DM is approved by the Federal Ministry of Research and Development (Bundesministerium fuer Forschung und Technologie).

Based on the IAG scientific assembly in Rio de Janeiro, Brazil, this volume combines papers in the fields of gravity and geoid, geodynamics, and geodesy in Antarctica. The volume contains papers on recent progress in absolute and relative gravimetry, on models of the global gravity field, theoretical developments in physical geodesy, and many examples of regional gravity field and geoid models. Geodynamics chapters include papers on earth rotation and geopotential variations, reference frames and global deformations, as well as a section on the combination of space and terrestrial methods for deformation observations. The current status of geodesy in Antarctica is illustrated by a number of papers.

Aerosols, which are gas-phase dispersions of particulate matter, draw upon and con tribute to multidisciplinary work in technology and the natural sciences. As has been true throughout the history of science with other fields of interest whose un derlying disciplinary structure was either unclear or insufficiently well developed to contribute effectively to those fields, "aerosol science" has. developed its own methods and lore somewhat sequestered from the main lines of contemporary physical thought. Indeed, this independent development is the essential step in which syste matic or phenomenological descriptions are evolved with validity of sufficient gen erality to suggest the potential for development of a physically rigorous and gen eralizable body of knowledge. At the same time, the field has stimulated many ques tions which, limited to its own resources, are hopelessly beyond explanation. As Kuhn pointed out in The Structure of Scientific Revolution 2nd enlarged edition (University of Chicago Press, Chicago 1970) Chapter II and Postscript-1969) this is a very common juncture in the development of a science. In brief, the transition from this earlier stage to the mature stage of the science involves a general re cognition and agreement of what the foundations of the field consist of. By this critical step, a field settles upon a common language which is well defined rather than the ambiguous, and often undefined descriptors prevalent at the earlier stage."

It is now a quarter of a century since Junge and his coworkers recovered the first sample from the sulfate aerosol layer in the stratosphere. Since that time vast strides have been made in determining its physical properties and morphology. These investigations have been performed with instruments on board aircraft and balloon platforms as in the early days, with ground-based lidar (optical radar), and most recently with satellite-borne optical instruments. It will become evident in Chapter 2 that in situ measurements by aircI'aft and, balloon sensors complement rather than duplicate the remote techniques (lidar and satellite). Hence future programs will probably continue to utilize direct as well as indirect experimental techniques. Concurrently, with the observations of the gross properties of the aerosol layer, la oratory and theoretical studies have sought to elucidate the chemical and micro physical processes which influence the formation and growth of the aerosol par ticles. The laboratory investigations have included studies of gas phase chemistry, and particle nucleation and growth mechanisms. Theoretical studies have revolved mainly around a series of models developed by atmospheric scientists. The earliest of these models was constructed by Junge and his colleagues. With the advent of third- and fourth-generation computers, the capacity to solve the quite complex continuity equations whi h govern particle formation, growth, and removal has ad vanced to the point where most of the particle properties can be simulated with reasonable confidence."

Computational methods and modelling is of growing importance in fundamental science as well as in applications in industry and in environmental research. In this topical volume the readers find important contributions in the field of turbulent boundary layers, the Tsunami problem, group invariant solution of hydrodynamic equations, non-linear waves, modelling of the problem of evaporation-condensation, the exact solution of discrete models of the Boltzmann equation etc. The book addresses researchers and engineers both in the mechanical sciences and in scientific computing.

The message of sunspots from the interior of the Sun to the Earth's climate When Galileo was summoned before the Inquisition on April 12, 1633, the main accusations laid against him concerned the doubts he expressed about Aristotle's theory of the universe. Aristotle's idea was that the Earth was the centre of the cosmos and that all of the stars, including the Sun, turned around it. Moreover, for Aristotle and the world of the Inquisitors, the Sun was a perfect celestial body. Now, Galileo had discovered spots on the Sun. These spots were seen as imperfections, and not just surface markings, but coming from within the Sun. Worse yet, they revolved around the Sun. All this supported the newfangled theory of Copernicus, and undermined a system of thought that had reigned supreme for centuries. Man of science that he was, and a prudent Catholic too, Galileo strived all his life to prove that Copernicus' astronomical concept was compatible with the word of the Bible. He proposed that there were not two truths but a single divine truth. It was just expressed in two different languages : there was the language of the common people, with its imprecision and inconsistencies, but intuitively understandable by everyone; and then there was the precise language of science with its strict regard for observation, which only a chosen few can grasp [L. Geymonat. 1992].

The aim of this book is to describe contemporary analytical and semi analytical techniques for solving typical celestial-mechanics problems. The word "techniques" is used here as a term intermediate between "methods" and "recipes." One often conceives some method of solution of a problem as a general mathematical tool, while not taking much care with its computa tional realization. On the other hand, the word "recipes" may nowadays be understood in the sense of the well-known book Numerical Recipes (Press et al., 1992), where it means both algorithms and their specific program realiza tion in Fortran, C or Pascal. Analytical recipes imply the use of some general or specialized computer algebra system (CAS). The number of different CAS currently employed in celestial mechanics is too large to specify just a few of the most preferable systems. Besides, it seems reasonable not to mix the essence of any algorithm with its particular program implementation. For these reasons, the analytical techniques of this book are to be regarded as algorithms to be implemented in different ways depending on the hardware and software available. The book was preceded by Analytical Algorithms of Celestial Mechanics by the same author, published in Russian in 1980. In spite of there being much common between these books, the present one is in fact a new mono graph."

This book is a study of plasma waves which are observed in the earth's magnetosphere. The emphasis is on a thorough, but concise, treatment of the necessary theory and the use of this theory to understand the manifold varieties of waves which are observed by ground-based instruments and by satellites. We restrict our treatment to waves with wavelengths short compared with the spatial scales of the background plasma in the mag netosphere. By so doing we exclude large scale magnetohydrodynamic phenomena such as ULF pulsations in the Pc2-5 ranges. The field is an active one and we cannot hope to discuss every wave phenomenon ever observed in the magnetosphere We try instead to give a good treatment of phenomena which are well understood, and which illustrate as many different parts of the theory as possible. It is thus hoped to put the reader in a position to understand the current literature. The treatment is aimed at a beginning graduate student in the field but it is hoped that it will also be of use as a reference to established workers. A knowledge of electromagnetic theory and some elementary plasma physics is assumed. The mathematical background required in cludes a knowledge of vector calculus, linear algebra, and Fourier trans form theory encountered in standard undergraduate physics curricula. A reasonable acquaintance with the theory of functions of a complex vari able including contour integration and the residue theorem is assumed."

To most people, travel is an exciting experience. When one journeys around the world, one is struck by the great variety and beauty of the landscapes that one encounters. The scientific mind, naturally, is not satisfied with admiring the various landscapes, but would like to understand how they were formed. The exact theory of landscape formation is a very com plicated affair, but much can be learnt from accurate observation. The need for the present little book became apparent to the writer during his studies of the mechanics oflandscape formation. It turned out that there was, in fact, no systematic compilation of those surface features of the Earth available, that have to be explained by theory. In effect, even the taxonomic principles that have to be applied in a classification of landscapes have nowhere been clearly stated. Thus, this book is intended to present a pictorial taxonomy of geomorphic features based on the basic principles of landscape genesis, as they have recently been worked out. The pictures have all been taken by the writer himself during many geoscientific studies and travels throughout the world. Some of these pictures had already been used in earlier publications of the writer's."

During the period April 25th to May 10th, 1984 the 3rd Course of the International School of Advanced Geodesy entitled "Optimization and Design of Geodetic Networks" took place in Erice. The main subject of the course is clear from the title and consisted mainly of that particular branch of network analysis, which results from applying general concepts of mathematical optimization to the design of geodetic networks. As al ways when dealing with optimization problems, there is an a-priori choice of the risk (or gain) function which should be minimized (or maximized) according to the specific interest of the "designer," which might be either of a scientific or of an economic nature or even of both. These aspects have been reviewed in an intro ductory lecture in which the particular needs arising in a geodetic context and their analytical representations are examined. Subsequently the main body of the optimization problem, which has been conven tionally divided into zero, first, second and third order design problems, is presented. The zero order design deals with the estimability problem, in other words with the definition of which parameters are estimable from a given set of observa tions. The problem results from the fact that coordinates of points are not univocally determined from the observations of relative quantities such as angles and distances, whence a problem of the optimal choice of a reference system, the so-called "datum problem" arises."

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.

Spacecraft study of the Solar system is one of humanity's most outstanding achievements. Thanks to this study, our present knowledge of properties of and conditions on the planets exceeds many-fold that of 20 years ago: planets have been rediscovered. This is especially the case for planetary atmospheres, whose properties were for the most part either not at all or only erroneously known. Much research has been invested in the study of the atmospheres of Mars and Venus, and their chemical composition and photochemistry are basic problems in these studies. In the present publication I have tried to summarize all findings in this field. The English version of the book includes new data in the field from the last 3 years since the book was published in Russian. I wish to thank U. von Zahn, who initiated my talks with Springer-Verlag and acted as technical editor. December 2, 1985 V. A. KRASNOPOLSKY Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 Chemical Composition and Structure of the Martian Atmosphere 4 1. 1 Carbon Dioxide and Atmospheric Pressure . . . . . . . . . . . . . . . . . . . 4 1. 2 CO and O Mixing Ratios . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2 1. 3 Ozone. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 1. 4 Water Vapor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 1. 5 Composition of the Upper Atmosphere as Determined from Airglow Spectroscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 1. 6 Mass Spectrometric Measurements of the Atmospheric Composition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 1. 7 Ionospheric Composition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 1. 8 Temperature Profile of the Lower Atmosphere. . . . . . . . . . . . . . . . 36 1. 9 Temperature of the Upper Atmosphere . . . . . . . . . . . . . . . . . . . . . . 40 1. 10 Eddy Diffusion Coefficient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 2 Photochemistry of the Martian Atmosphere . . . . . . . . . . . . . . . . . .

The book is based on an international workshop on High Precision Navigation. The reader will find a wealth of information on - satellite navigation systems and their geodetic applications, especially using GPS - laser and radar techniques - image processing and image sequence analysis - autonomous vehicle guidance systems - inertial navigation systems - integration of different sensor systems.