to Mission Design for Geostationary Satellites by J.J. Pocha British Aerospace, Space and Communications Division, Steven age, u.K. D. Reidel Publishing Company A MEMBER OF THE KLUWER ACADEMIC PUBLISHERS GROUP Dordrecht / Boston / Lancaster / Tokyo Library of Congress Cataloging in Publication Data Pocha, J. J. (Jehangir. J.), 1945- An introduction to mission design for geostationary satellites. (Space technology library) Includes bibliographies and index. 1. Geostationary satellites. 2. Artificial satellites in telecommunica tion. I. Title II. Series. TK5104.P63 1987 621.38'0423 87-4909 ISBN-13: 978-94-010-8215-0 e-ISBN-13: 978-94-009-3857-1 DOl: 10.1007/978-94-009-3857-1 Published by D. Reidel Publishing Company, P.O. Box 17, 3300 AA Dordrecht, Holland. Sold and distributed in the U.S.A. and Canada by Kluwer Academic Publishers, 101 Philip Drive, Assinippi Park, Norwell, MA 02061, U.S.A. In all other countries, sold and distributed by Kluwer Academic Publishers Group, P.O. Box 322, 3300 AH Dordrecht, Holland."

The material given in this 'Introduction to astronomical photometry' is the subject matter of a lecture at the University of Geneva. It is, therefore, intended for those students, physicists or mathematicians, who have completed their bachelor's degree or diploma, and are intending to work for their Ph.D. in astronomy. We assume then the elementary ideas of astrophysics, magnitude, colour index, spectral classes, luminosity classes, gradient, atmospheric extinction are already known. The student may find it useful to re-read the work of Schatzman [1], Dufay [2] and Aller [254] before embarking upon the study of this 'Introduction to astronomical photometry'. It is not our aim in this book to deal with every aspect of stellar photometry. On the contrary, we shall restriet ourselves to looking at subjects ofwhich knowledge seems to us essential for someone who has to use photometrie quantities in his astronomical research. We are, therefore, keeping the interests of the photometrie measurements user partieularly in mind. We shall only discuss very superficially the technical prob lems and reduction methods for atmospheric extinction. These problems are dealt with very clearly in Astronomical Techniques [3]; the first by A. Lallemand, H. L.

After the same pattern as the XIII th General Assembly of the International Astronom ical Union the present Volume of the Highlights in Astronomy contains the texts of the invited discourses given at the XIVth General Assembly held in Brighton, England, August 1970. It contains further the papers and discussion remarks presented at the six joint discussions, as well as the invited papers given at the special session on the Moon. In addition this Volume contains the papers given at the joint meeting of Commissions 24, 27, 30, 33 and 37 on RR Lyrae Stars. It goes without saying that the nearly hundred papers printed in this Volume represent only a minor part of all matter dealt with at the XIVth General Assembly of the Union; the many important discussions that took place in a few hundred commission meetings are not included. For short abstracts and reviews of these the reader is referred to Transactions of the International Astronomical Union XIVB. I wish to thank those who contributed to this Volume for the speed in submitting the manuscripts of their papers. This, together with the efficiency of the Publishers allowed for a rapid publication.

In 1995, the German Space Agency DARA selected the CHAllenging Minisatellite Payload (CHAMP) mission for development under a special support programme for the space industry in the new states of the unified Germany, with the Principal Investigator and his home institution GFZ Potsdam being ultimately responsible for the success of all mission phases. After three years of spacecraft manufactur ing and testing, the satellite was injected successfully into its final, near circular, almost polar and low altitude (450 km) orbit from the cosmodrome Plesetsk in Russia on July 15, 2000. After a nine month commissioning period during which all spacecraft systems and instruments were checked, calibrated and validated, the satellite has been delivering an almost uninterrupted flow of science data since May 2001. Since this date, all science data have been made available to the more than 150 selected co-investigator teams around the globe through an international Announcement of Opportunity. The scientific goals of the CHAMP mission are to gain a better understanding of dynamic processes taking place in the Earth's interior and in the space near Earth. These goals can be achieved by improved observation of the Earth's gravity and magnetic fields and their time variability with high-performance on-board instru mentation and by exploring the structure of the Earth's atmosphere and ionosphere through radio occultation measurements.

This volume contains the detailed text of the lectures delivered at the International Workshop on Space Dynamics and e*elestial Mechanics held in Delhi, India during November 14-16,1985. This workshop was organised under the joint sponsorship of University of Delhi, Delhi, Vikram Sarabhai Space Centre, Trivandrum (India) and the Space Programme of the University of Texas at Austin, Austin, USA. The main objective of the workshop was to review the current state of the art in the area of Space .Dynamics and Celestial Mechanics thr- ough paper presentations, key note addresses, lectures and discussions, to expose the participants to more recent developments in varjous tech- niques, analytical as well as numerical, as applicable to Space Mecha- nics, to identify and assess the degree of augmentations desirable in respect of software packages available for this purpose with different centres and to establish contacts with experts in the vital field with a view to facilitate the in flow of technical inf~rmation. The whole material of this volume has been organized into seven basic areas: (i) The key note address by Professor V. Szebehely, (ii) General Celestial Mechanics, (~ii) Solar System and Natural Satellites, (iv) Stellar Systems and Galaxies, (v) Orbit Determination and Satellite Theory, (vi) Attitude Motion and (vii) Mission Planning and Control.

IAU Symposium Number 52 on Interstellar Dust and Related Topics was held at Albany, N.Y., on the campus of the State University of New York at Albany from May 29 to June 2, 1972. The members of the Organizing Committee were: Dr A. D. Code, University of Wisconsin, Madison, Wis., U.S.A. Dr B. D. Donn, Goddard Space Flight Center, Greenbelt, Md., U.S.A. Dr A. Elvius, Stockholm Observatory, Saltsjobaden, Sweden. Dr T. Gehrels, Lunar and Planetary Laboratory, University of Arizona, Tucson, Ariz., U.S.A. Dr J. M. Greenberg (Chairman), State University of New York at Albany, Albany, N.Y., U.S.A. Dr H. C. van de Hulst, Sterrewacht, Leiden, Holland. Dr S. B. Pikel'ner, Sternberg Astronomical Institute, Moscow, U.S.S.R. Dr E. E. Sal peter, Cornell University, Ithaca, N.Y., U.S.A. Dr B. E. Turner, National Radio Astronomy Observatory, Charlottesville, Va., U.S.A. The suggestion was first made in 1971 that a symposium on interstellar grains would be timely. The response to the first preliminary announcement, which was sent out on November 29, 1971, was well beyond our expectations. The meeting was locally sponsored by the State University and by Dudley Observatory. The National Aeronautics and Space Administration and the National Science Foundation con tributed along with the JAU. There were 158 participants of whom 49 were from 15 countries outside the United States. A total of 92 papers were presented.

This monograph is devoted to the basic aspects of the physics of highly ex cited (Rydberg) states of atom's. After almost twenty years, this remains a hot topic of modern atomic physics. Such studies are important for many areas of physics and its applications including spectroscopy, astrophysics and radio astronomy, physics of electronic and atomic collisions, kinetics and di agnostics of gases, and low- and high-temperature plasmas. Physical phenom ena in radiative, collisional, and spectral-line broadening processes involving Rydberg atoms and ions are primarily determined by the peculiar properties and exotic features of highly excited states. The growth of interest and research activity in the physics of Rydberg the last two decades was stimulated by an extremely rapid de atoms over velopment of high-resolution laser spectroscopy, methods of selective excita tion and detection of highly excited states, atomic-beam techniques as well as radio astronomy. This has facilitated significant progress in the differ ent directions of the physics of highly excited atoms being of fundamental and practical importance. In particular, evident advances were achieved in studies of the structure and spectra of highly excited atoms, their behavior in static electric and magnetic fields, interactions with electromagnetic ra diation, spectral-line broadening and the shift of Rydberg series, collisions with electrons, ions, atoms, and molecules, etc. The principle objective of the present book is to reflect the most important physical approaches and efficient theoretical techniques in the modem physics of highly excited atoms and ions."

The papers in this volume were delivered and responded to at the Third Conference of the International Society for the Study of Time. The meeting took place during sunny days, punctuated by an occasional brief storm, in the confer ence facilities of the OEsterreichisches College in Alpbach, Austria, from ]uly 1 to ]uly 10, 1976. In the middle of it came ]uly 4, the 200th anniversary of the Declaration ofindependence, and in honor ofparticipants from the United States there was a special session of papers on the subject of Freedom and Time. [See Fraser, Park in this volume. ] The effect of the papers was kaleidoscopic; reading the table of contents one can surmise the experience of those enthusiasts, and there were several, who heard them all. I think that most people who have been puzzled about time will agree that it is not clear wh at the puzzle is or from what direction the insights will come that will enable us to understand the situation a litde more clearly. As one of the participants wrote afterwards, "After all , we do not know apriori whether there exists areal unity in studies about time, but if one exists it must reveal itself progressively in the course of successive experiences such as these lectures. If it were easy to find, it would have been found already without the Society's help.

This book is an outgrowth of the notes made for the semester lectures on 'Problems of Extragalactic Astronomy' given almost annually during two decades at the Ob- servatorio Astronomico of the Universidad de Cordoba. Shorter versions were also given at La Plata, Santiago de Chile, Sao Paulo, Rio de Janeiro and Paraiba. E. Scalise made a Portuguese language version of the notes and encouraged me to publish them; although my friend J. Kleczek is to be blamed for the idea of this book. Not every subject on Extragalactic Astronomy has been touched in this book: instead I have followed those which interested me during 25 years of professional practice in this part of the world. I acknowledge helpful suggestions from M. Pastoriza and G. Carranza, the com- prehension of Director L. Milone, and the collaboration of the staff of the Observa- tory in Cordoba. R. Tschamler's humor and wit made light the task of producing the English version and M. Pizarro's devotedness produced the edited MS. To both of them I am in deep gratitude. "A book is published out of necessity, otherwise the author would spend his entire life polishing the originals" was the answer given by J. L. Borges to an inquisi- tive journalist. These words explain why this book is so different from the lecture notes, and also from the book I was hoping for. I thank B. McCormac and the D. Reidel Publ. Co. for my salvation from Borges' inferno.

The lAU Colloquium No. 56, the Second lAU Colloquium, "On Reference Coordinate Systems for Earth Dynamics," co-sponsored by the COSPAR and the International Association of Geodesy of IUGG was held in Warsaw, Po1and, on September 8-12, 1980. The Co11oquium was organized by the Space Research Centre of the Po1ish Academy of Sciences and the Smithsonian Institution Astrophysica1 Observatory. It was sponsored by the Committee of Astronomy, the Committee of Geodesy, and the Committee of Space Research of the Po1ish Academy of Sciences. The first Co11oquium devoted to this subject was held in Torun, Po1and, in 1974. The Scientific Organizing Committee consisted of: Cochairmen Dr. E. M. Gaposchkin USA Dr. B. Ko~aczek Po1and Members of the Program Committee Prof. J. Kova1evsky France Prof. I. I. Mueller USA Prof. M. Rochester Canada Members Dr. M. Bursa Czechos1ovakia Dr. H. K. Eichhorn USA Prof. W. Fri cke FRG Dr. E. Hog Denmark Dr. Y. Kozai Japan Dr. Y. S. Yatskiv USSR The Loca1 Organizing Committee consisted of: Dr. B. Ko~aczek, Chairman Dr. W. Pache1ski, Secretary Dr. W. Dobaczewska Dr. J. Krynski Dr. G. Sitarski Prof. J. Smak Dr. J. B. Zielinski Mr. W. Zarnowiecki ix E. M. Gaposchkin and B. Kotaczek (eds. ), Reference Coordinate Systems for Earth Dynamies, ix-x. Copyright (c) 1981 by D. Reidel Publishing Company. x PREFACE The duties of chairmen of the sessions were performed by Dr. J. Zielinski, Dr. P. Bender, Prof. W. Fricke, Dr. B.

In the twenties the new atomic physics opened the way toward a quantitative interpretation of stellar spectra. It was one of the aims in this new branch of astrophysics to determine in a quantitative way the chemical composition of stellar atmospheres, i. e. of those parts of the stars which are accessible to spectro scopic observation. It was only in the forties that the first reasonably accurate and complete analyses became available. In the meantime nuclear physics and the theory of the internal constitution of the stars had reached the important conclusion that the main sequence of the Hertzsprung-Russell-diagram is taken up by stars which in their central parts produce energy by the conversion of hydrogen into helium. It was BAADE who in the early fifties stimulated observational and theoretical work concerning the colour-magnitude-diagrams of star clusters and their connection with the nuclear evolution of stars. Obviously, this type of research opened also the way towards much more difficult and far reaching fields of research: the formation of galaxies and the origin of the chemical elements and their abundance distributions."

One of the most fundamental discoveries of the solar system was the detection of four moons in orbit around Jupiter by Galileo Galilei in 1610. The discovery was significant not only in the context of Jupiter; it gave credence to and was instrumental in firmly establishing the heliocentric system of Nicolaus Copernicus. Almost four centuries after Galileo's discovery, exten sive observations by the two Voyager spacecrafts have once again revolu tionized our thinking about the major planets, their composition, structure, origin, and evolution. This book is an attempt at summarizing our present understanding of the atmospheres and ionospheres in the outer solar system, with particular emphasis on the relevant physics and chemistry. I was motivat ed to prepare this manuscript for the following reasons. First, after under going rapid expansion in the recent past, the subject has finally attained suf ficient maturity to warrant a monograph of its own. Second, I have felt that as a result of recent observations, new and challenging problems have arisen whose resolution requires unconventional analysis and theoretical interpreta tion of existing data, as well as the collection of new kinds of data. I believe the time is ripe to put these issues in the appropriate scientific perspective, with the hope of stimulating novel theoretical, observational, and laboratory studies. I have highlighted the significant scientific problems throughout the book, especially at the end of each chapter.

The underlying astrophysical mechanisms of the objects known as asymptotic giant branch stars - the structures that occur during the dramatic period prior to a star's death - is the main theme of this text. Over the past three decades, asymptotic giant branch stars have become a topic of their own, and the contributions to this volume all focus on these entities themselves, rather than their connections to other fields of astronomy. Among the many topics covered are new methods of high- quality infrared observation and the more detailed and realistic simulations made possible by increasingly fast computers. This collection should be useful to graduate students who work in the field, teachers who want to address the subject in their courses, and to astronomers from various backgrounds who are interested in the astrophysics of AGB stars.

In May 1986 a two-day workshop on Physical Processes in Comets, Stars and Active Galaxies was held at the Ringberg Castle near Lake Tegernsee, and this rather unusml. l collection of topics needs a few words of explanation. When we first thought of organizing a workshop on such a large variety of astrophysical objects our main motivation was to honor Rudolf Kippenhahn and Hermann Ulrich Schmidt on the occasion of their 60th birthdays, and we planned to cover at least a fraction of their fields of active research. We then realized immediately that despite the fact that the objects are so different, the physical processes involved are very much the same, and that it is this aspect of astrophysics which governed the scientific lives of both of our distinguished colleagues and friends and allowed them to make major contributions to all those fields. Apparently this viewpoint was shared by many colleagues and it was therefore not surprising that in response to our invitation everybody who had been invited agreed to come and to present a talk. The workshop then turned out to be a real success. In contrast to highly specialized conferences, fundamental problems as well as very recent devel opments were discussed and the participants appreciated the opportunity to exchange ideas."

The yearbook series Reviews in Modern Astronomy of the Astronomische Gesell three years ago in order to bring the scientific events schaft (AG) was established of the meetings of the society to the attention of the worldwide astronomical community. Reviews in Modern Astronomy is devoted exclusively to the invited reviews, the Karl Schwarzschild lectures, and the highlight contributions from leading scientists reporting on recent progress and scientific achievements at their research institutes. Volume 4 comprises all, eighteen contributions which were presented during the fall meeting of the AG at Preiburg/Breisgau in September 1990. They cover problems in solar research and the solar system as well as the first results of the ROSAT and Hipparcos space missions, stellar and extragalactic studies, and Supernova 1987A in the Large Magellanic Cloud. The Karl Schwarzschild Medal was awarded to Professor Eugene Parker1. His lecture entitled "Convection, Spontaneous Discontinuities, and Stellar Winds and X-Ray Emis*sion" begins this volume.

In the course of editing this volume I discovered that I am temper amentally unsuited to the task, an impediment that in no small way accounts for the fact that its publication is later than I would have hoped or anticipated. I am, at heart, a pedant, particularly with respect to the use and abuse of the English language. Many of my scientific colleagues are a good deal less punctilious; they take the reasonable view that if the message is clear, the manner of expression is unimportant. Experience has taught me that what is clear to the author is often quite unclear to the reader unless the author takes the trouble to express himself with precision. I have also found that most scientists are unwilling to devote to the presentation of their results the care that they lavish on obtaining them. But I found myself slipping beyong this often justifiable complaint into a state of inexcusable self-righteousness. It began innocently enough. Conscious of the need for speed, I read the first two or three texts with murmurs of approval, and scribbled 'no changes needed' on the title page of the copy. Then I began to notice one or two grammatical mistakes, plural verbs with singular nouns, mixtures of tenses, and so on, which had to be corrected; not serious, I told myself, a matter only of changing a word here, retyping a line there. Quickly I sank deeper."

The Little Book of Stars answers, in the clearest language, the questions anyone might have about our heavenly canopy. How are stars born? How do they die? Why do they shine? How long do they shine? Is our star, the Sun, dying? How can you tell time from the stars? Or navigate? What are the measures of stars? Can we ever travel to other stars? In this engagingly written and concise book, the second in the Little Book series, noted astronomer James B. Kaler shows us "the significance that the stars have had in human life, how we have used them to tell our stories, and how we use them to find who and where we are."

Interstellar matter is one of the most active fields of research in present-day astronomy. Observational information spans the full electromagnetic spectrum from gamma rays through rocket-ultraviolet, optical, infrared and millimeter to long radio waves. Results of research in physical chemistry find as much application as mathematical methods. Interstellar matter plays a leading role in studies of our Galaxy and of external galaxies, and contributes increasingly to stellar astronomy. At the 16th General Assembly of the International Astronomical Union, held in August 1976 in Grenoble, France, the many new developments in this vast field were surveyed in a number of sessions of Commission 34 (Interstellar Matter), mostly jointly with other Commissions of the Union. Separate sessions were devoted to: The hot interstellar gas phase, Interaction of stars and interstellar medium, Interstellar molecules and dust, The large-scale distribution of interstellar matter in the Galaxy, and Interstellar matter in external galaxies. Twenty-four invited review papers were presented and discussed in these sessions. The quality and success of these topical reviews made it seem desirable to make them available to a wider audience. Professor Edith Muller, the new General Secretary of the IAU, enthusiastically supported the idea. Most importantly, the reviewers - who had originally been pro mised that an oral paper was the only requirement - agreed to prepare written versions. I am grateful to Mrs. Muller, to the authors, and to Reidel Publishing for their collaboration in the preparation of this book."

This book, in three parts, describes three phases in the development of the modern theory and calculation of the Moon's motion. Part I explains the crisis in lunar theory in the 1870s that led G.W. Hill to lay a new foundation for an analytic solution, a preliminary orbit he called the "variational curve." Part II is devoted to E.W. Brown's completion of the new theory as a series of successive perturbations of Hill's variational curve. Part III describes the revolutionary developments in time-measurement and the determination of Earth-Moon and Earth-planet distances that led to the replacement of the Hill-Brown theory in 1984.

Little more than ten years have passed since spaceprobe-borne instruments con clusively demonstrated the existence of the solar wind. These observations con firmed the basic validity of a theoretical model, first proposed by E. N. Parker, predicting a continuous, rapid expansion of the solar corona. The subsequent decade has seen a tremendous growth in both the breadth and sophistication of solar wind observations; the properties of the interplanetary plasma near the orbit of the earth are now known in great detail. The theory of the coronal ex pansion has also been highly refilled both in the sense of including additional physical processes, and of treating more realistic (time-dependent and non spheri cally-symmetric) coronal boundary conditions. The present volume is an attempt to synthesize the solar wind observations and coronal expansion models from this decade of rapid development. The ultimate goal is, of course, the interpretation of observed solar wind phenomena as the effects of basic physical processes occurring in the coronal and interplanetary plasma and as the natural manifestations of solar properties and structures. This approach implies an emphasis upon the "large-scale" features revealed by the observations. It requires extensive use of the concepts and methods of fluid mechanics."

Professor Zdenek Kopal is sixty-seven this year even though his scientific activity, enthusiasm and springy step hardly betray the ad- vancement in years. He carne to Manchester as Professor of Astronomy thirty years ago after a very fruitful association of fourteen years with the Harvard Observatory. Much impressed with the young man, Harlow Shapley, who with characteristic insight had recognised in Kopal the qualities that have since made him an outstanding leader in ec1ipsing binary research, had invited him over as a Research Associate. In the subsequent decade Kopal set about the task of introducing analytical rigour in the solution of orbit al elements that hitherto had depended ex- c1usively on the semigraphical procedures introduced by Russell and exploited fully by Shapley. These first efforts stimulated publication of the first of his many books on ec1ipsing variables; the Introductian ta the Study of Ec/ipsing Variables summarized these iterative methods and remains a c1assic in this field. Soon after the appearance of this volume in print, Kopal gave a course on this subject for the graduate students at Harvard. I was one of those who had the opportunity to attend it and learn much on the need of care and precision in the practice of photoelectric photometry and the importance of exploiting such data to the fullest extent with methods of increasing resolving power.

With the discovery of pulsars, quasars, and galactic X-ray sources in the late 60's and early 70's, and the coincident expansion in the search for gravitational waves, rela tivistic gravity assumed an important place in the astrophysics of localized objects. Only by pushing Einstein's solar-system-tested general theory of relativity to the study of the extremes of gravitational collapse and its outcomes did it seem that one could explain these frontier astronomical phenomena. This conclusion continues to be true today. Relativistic gravity had always played the central role in cosmology. The discov ery of the cosmic background radiation in 1965, the increasing understanding of matter physics at high energies in the decades following, and the growing wealth of observations on the large scale structure meant that it was possible to make increasingly detailed mod els of the universe, both today and far in the past. This development, not accidentally, was contemporary to that for localized objects described above."

20* * 0 0_ >.1

M. M. Shapiro and J. P. Wefel AN OVERVIEW OF COSMIC RAY RESEARCH: COMPOSITION, ACCELERATION AND PROPAGATION J. P. Wefel PROPAGATION AND TRANSFOR'1ATIONS OF cosme RAYS: 41 FROM SOURCES TO EARTH R. Silberberg, C. H. Tsao, J. R. Letaw and M. M. Shapiro 71 ULTRA HEAVY NUCLEI IN THE COSMIC RADIATION W. R. Binns GALACTIC COSMIC RAY HYDROGEN AND HELIUM 91 J. J. Beatty COSMIC RAYS OF THE HIGHEST ENERGIES 97 J. Szabelski STARS AND COSMIC RAYS 105 I. COOL STARS T. Montmerle STARS AND COSMIC RAYS 131 II. HOT STARS T. Montmerle ON THE POSSIBLE CONTRIBUTION OF WC STARS TO ISOTOPIC 153 ANOMALIES IN COSMIC RAYS AND METEORITES J. B. Blake and D. S. P. Dearborn GAMMA-RAY VIEWS ON THE GALACTIC COSMIC-RAY DISTRIBUTION 163 H. Bloemen VlIl RADIO ASTRONOMY AND COSMIC RAYS 175 K. W. Weiler PARTICLE ACCELERATION IN GALACTIC SUPERNOVA REMNANTS 205 D. A. Green PULSARS AS COSMIC RAY PARTICLE ACCELERATORS -- NEW RESULTS 215 ON THE DYNAMICS OF PROTONS IN VACUUM FIELDS K. o. Thie1heim CONDITIONS FOR ACCELERATION OF SUPER-HIGH ENERGY COSMIC RAYS 227 IN ACTIVE GALACTIC NUCLEI W. H. Sorrell COSMIC RAYS AND A STABLE HYDROSTATIC EQUILIBRIUM OF THE GALAXY 235 H. B10emen VRE AND URE GAMMA P Y OBSERVATIONS BY GROUND BASED 241 DETECTORS W. Stamm 15 HADRON AND MUON COMPONENTS IN PHOTON SHOWERS AT 10 eV 255 Ch. P. Vankov and J. N. Stamenov MONOPOLES, MUONS, NEUTRINOS AND CYGNUS X-3 261 M. L. Cherry, S. Corbato, D. Kieda, K. Lande, and C. K.

The Sixth European Regional Meeting in Astronomy (VI ERMA) on "Sun and Planetary System" was held in Dubrovnik (Yugoslavia), 19-23 October 1981, sponsored by the Federal Executive Council of Yugoslavia, the IAU, IUGG, and the European Physical Society. The Scientific Organizing Committee included W. Fricke (Chairman), H. Alfven, H. Haupt, H. Kautzleben, Z. Kopal, J. Kovalevsky, V. A. Krat, L. Kresak, G. Marx, P. Melchior, P. J. Message, J. -C. Pecker, G. Sitarski, B. Sevarlic, G. Teleki, and R. M. West. The Local Organizing Committee representing the Union of Societies of Mathematicians, Physicists and Astronomers, Yugoslavia, included G. Teleki (Chairman), I. Pakvor (Vice-Chairman), Z. Knezevic (Secretary), B. Jovanovic, L. Randic, P. Ranzinger, V. Ruzdjak, B. Popovic, and B. Sevarlic. The Meeting was attended by 216 participants from 27 countries (5 continents). The scientific programme was divided into the following five sections: (1) Sun from the astronomical and physical points of view (main organizer: J. -C. Pecker); (2) Astronomical, geophysical and geodetic problems related to the Earth (main organizer: J. Kovalevsky); (3) Physics of planets, minor planets, satellites and interplanetary medium (main organizer: Z. Kopal); (4) Motions in the planetary system (main organizer: L. Kresak); (5) Three dimensional refraction (main organizer: G. Teleki). Ten invited review papers were presented in 5 plenary sessions; 20 invited papers and about 100 contributed papers were presented in parallel sessions."