Since the 1970s symposia or colloquia devoted to recent research on close binaries have been held around the world almost annually. At meetings of the General Assembly of the International Astronomical Union this topic has also been discussed in detail at presentations in various commission meetings and also as invited talks by leading astronomers in the field. In recent years, fundamental changes have taken place in the study of close binaries due to the improvements in observational techniques, extension of observations from X-ray to radio regions of the electromagnetic spectrum, and advances in theoretical studies. For more than a decade, a group of astronomers at Ege University Observatory has been concentrating on active close binaries with particular emphasis on the behaviour of the light curves of chromospherically active systems. Thus, we decided to organize an international meeting in Western Anatolia, where this part of Turkey had been the cradle for great developments in science during antiquity. KUljadasi, located only minutes away from Ephesus, one of the seven wonders of the world, was selected to be the meeting site. Close binary systems constitute a very rich source of information about the physical properties of the component stars. Some systems are eclipsing variables, where periodic recurrences of eclipses are observed as comparatively brief decreases in the total brightness of the binary system. Precise methods of photometric observations make it possible to obtain the light variations of these systems because of eclipses and other phenomena.

Viewed as a flashpoint of the Scientific Revolution, early modern astronomy witnessed a virtual explosion of ideas about the nature and structure of the world. This study explores these theories in a variety of intellectual settings, challenging our view of modern science as a straightforward successor to Aristotelian natural philosophy. It shows how astronomers dealt with celestial novelties by deploying old ideas in new ways and identifying more subtle notions of cosmic rationality. Beginning with the celestial spheres of Peurbach and ending with the evolutionary implications of the new star Mira Ceti, it surveys a pivotal phase in our understanding of the universe as a place of constant change that confirmed deeper patterns of cosmic order and stability.

Ptolemy was the most important physical scientist of the Roman Empire, and for a millennium and a half his writings on astronomy, astrology, and geography were models for imitation, resources for new work, and targets of criticism. Ptolemy in Perspective traces reactions to Ptolemy from his own times to ours. The nine studies show the complex processes by which an ancient scientist and his work gained and subsequently lost an overreaching reputation and authority.

Because of recent progress in the development of quasistationary toroidal mag- netic confinement systems, especially tokamaks, these systems are at the center of research on controlled thermonuclear fusion. Tokamaks were proposed and first built at the Kurchatov Institute of Atomic Energy. In the 1960s the basic features of plasma behavior in toroidal magnetic confinement systems were investigated in ex- periments on the first tokamaks and the possibility of obtaining effective confine- ment in them was demonstrated. The successes of this first stage led to a rapid ex- pansion in tokamak research around the world. The development of a thermonu- clear power reactor based on the tokamak is now actively under way. During the earliest phase of research on tokamaks, it was already clear that the ohmic heating used in them was not sufficient to obtain the temperatures needed for initiation of a self-sustaining thermonuclear reaction. At the beginning of the 1970s, therefore, a search was begun for methods of heating which could supple- ment ohmic heating. The best of these auxiliary heating techniques are neutral beam injection, various methods based on the collisionless absorption of rf (radio fre- quency) waves, and adiabatic compression of the plasma by a rising magnetic field.

I was introduced to Tiisi: and his Tadhkira some 19 years ago. That first meeting was neither happy nor auspicious. My graduate student notes from the time indicate a certain level of confusion and frustration; I seem to have had trouble with such words as tadwlr (epicycle), which was not to be found in my standard dictionary, and with the concept of solid-sphere astronomy, which, when found, was pooh-poohed in the standard sources. I had another, even more decisive reaction: boredom. Only the end of the term brought relief, and I was grateful to be on to other, more exciting aspects of the history of science. A few years later, I found myself, thanks to fellowships from Fulbright-Hays and the American Research Center in Egypt, happily immersed in the manu script collections of Damascus, Aleppo, and Cairo. Though I had intended to work on a topic in the history of mathematics, I was drawn, perhaps inevitably, to a certain type of astronomical writing falling under the rubric of hay' a. At first this fascination was based on sheer numbers; that so many medieval scientists could have written on such a subject must mean something, I told myself. (I was in a sociological mode at the time.

Ram accelerators are among the most advanced tools for generating fluid dynamcis data in supersonic reacting systems. They require the combined action of combustion, wave systems and turbulence and are still a serious challenge for physicists and engineers. This book will serve as an introductionary textbook on ram accelerators and gives a thorough overview on research activities, performance modeling and high-pressure detonation dynamics.

After the launching of the first artificial satellites preceding interplanetary vehicles, celestial mechanics is no longer a science of interest confined to a small group of astronomers and mathematicians; it becomes a special engineering technique. I have tried to set this book in this new perspective, by severely limiting the choice of examples from classical celestial mechanics and by retaining only those useful in calculating the trajectory of a body in space. The main chapter in this book is the fifth, where a detailed solution is given of the problem of motion of an artificial satellite in the Earth's gravitational field, using the methods of Von Zeipel and of Brouwer. It is shown how Lagrange's equations can be applied to this problem. The first four chapters contain proofs of the main results useful for these two methods: the elliptical solution of the two-body problem and the basic algebra of celestial mechanics; some theorems of analytical mechanics; the Delaunay variables and the Lagrangian equations of variation of elements; the expansion of the disturbing function and the Bessel functions necessary for this expansion. The last two chapters are more descriptive in character. In them I have summarized briefly some of the classical theories of celestial mechanics, and have tried to show their distinctive characteristics without going into details.

The concept of infinity is one of the most important, and at the same time, one of the most mysterious concepts of science. Already in antiquity many philosophers and mathematicians pondered over its contradictory nature. In mathematics, the contradictions connected with infinity intensified after the creation, at the end of the 19th century, of the theory of infinite sets and the subsequent discovery, soon after, of paradoxes in this theory. At the time, many scientists ignored the paradoxes and used set theory extensively in their work, while others subjected set-theoretic methods in mathematics to harsh criticism. The debate intensified when a group of French mathematicians, who wrote under the pseudonym of Nicolas Bourbaki, tried to erect the whole edifice of mathematics on the single notion of a set. Some mathematicians greeted this attempt enthusiastically while others regarded it as an unnecessary formalization, an attempt to tear mathematics away from life-giving practical applications that sustain it. These differences notwithstanding, Bourbaki has had a significant influence on the evolution of mathematics in the twentieth century. In this book we try to tell the reader how the idea of the infinite arose and developed in physics and in mathematics, how the theory of infinite sets was constructed, what paradoxes it has led to, what significant efforts have been made to eliminate the resulting contradictions, and what routes scientists are trying to find that would provide a way out of the many difficulties.

This collection of 7 lectures is intended to be a textbook for graduate students who want to learn about modern developments in astronomy and astrophysics. The first part surveys various aspects of the late stages of stellar evolution, including observation and theory. B.C. de Loore's long article on stellar structure is followed by reviews on supernovae, on circumstellar envelopes, and on the evolution of binaries. The second part deals with the important problem of modeling stellar evolution based on the computational hydrodynamics.

The Ionospheric Institute of the National Observatory of Athens has had two interests in recent years: the study of the ionosphere and the study of the sun. In our previous Advanced Study Institutes in 1960, 1961, and 1962, we have em phasized the ionosphere. For the Advanced Study Institute of 1964, however, we invited Dr. Jules Aarons of the Air Force Cambridge Research Laboratories to collaborate in preparing and directing a program of studies of the sun, the moon, the planets, and the interplanetary medium. The lectures of this Advanced Study Institute form essentially an advanced course in radio astronomy. Without being a textbook on the matter, we feel that the present book can be considered as an excellent reference for those students starting their research work in the field of solar system radio astronomy. All lecturers tried to present their subjects in a simple form based upon their exten sive personal experience, but without emphasizing their personal research. We must recognize that it was an excellent achievement for them to keep their text exactly at the level indicated by the Program Director, and outlined by the gen eral program of Advanced Study Institutes of NATO. We are deeply grateful to all the invited scientists for their outstanding contributions in lecturing on their subjects in a clear and authoritative manner. The Scientific Affairs Division of NATO, in its aid to basic research, spon sors various programs. Among them is the Program of Advanced Study Institutes."

For this set of lectures we assumed that the reader has a reasonable back ground in physics and some knowledge of general relativity, the modern theory of gravity in macrophysics, and cosmology. Computer methods are present ed by leading experts in the three main domains: in numerics, in computer algebra, and in visualization. The idea was that each of these subdisciplines is introduced by an extended set of main lectures and that each is conceived as being of comparable 'importance. Therefpre we believe that the book represents a good introduction into scientific I computing for any student who wants to specialize in relativity, gravitation, and/or astrophysics. We took great care to select lecturers who teach in a comprehensible way and who are, at the same time, at the research front of their respective field. In numerics we had the privilege of having a lecturer from the National Center for Supercomputing Applications (NCSA, Champaign, IL, USA) and some from other leading institutions of the world; visualization was taught by a visualization expert from Boeing; and in com puter algebra we took recourse to practitioners of different computer algebra systems as applied to classical general relativity up to quantum gravity and differential geometry.

This volume is a collection of experimental and theoretical papers presented at the international "Topical Meeting on Optical Bistability," held at the University of Rochester, June 15-17, 1983, sponsored jointly by the Air Force Office of Scientific Re search; the Army Research Office; and the Optical Society of America. The Conference, which had 150 attendees, overlapped (on June 15) with the Fifth Rochester Conference on Coherence and Quantum Optics with two joint sessions. Some of the topics cover ed in this volume are also treated io the Proceedings of that Conference. Since the last international conference on Optical Bistability, held in Asheville, North Carolina, June 3-5, 1980, there have been new and important fundamental advances in the field. This is borne out in papers in this volume dealing with optical chaos and period doubling bifurcations leading to chaos as well as the report of results of an experiment using a very simple system exhibiting ab sorptive optical bistability in a ring cavity using optically pump ed sodium atoms, which was successfully analyzed quantitatively by a simple theory. Other advances discussed here include the ob servation of optical bistability due to the effect of radiation pressure on one mirror of a fabry-Perot cavity. and the prediction of mirrorless intrinsic opittal bistability due to the local field correction incorporated into the Maxwell-Bloch formulation. Advances in optical bistability in semiconductors relate closer to actual device applications."

This book deals with the fundamentals of stellar interferometry with emphasis on aperture synthesis using sparse array of telescopes particularly at optical/IR wavelengths, the origin, properties, and optical effects of turbulence in the Earth's atmosphere, techniques developed to overcome image degradation. Studded with more than one hundred and fifty illustrations and tens of footnotes, it addresses the basic tricks of trade, current trend, motivation, methods, and path to future promise of true interferometry both from the ground and space. Also discussed are the technical challenge involved, such as beam transportation and recombination, detecting fringes using modern sensors, and image synthesis. Astronomical science that benefits from aperture synthesis imaging are highlighted as well.

Light scattering and absorption by small homogeneous particles can be worked-out exactly for spheres and infinite cylinders. Homogeneous particles of irregular shapes, when averaged with respect to rotation, have effects that can in general be well-approximated by reference to results for these two idealised cases. Likewise, small inhomogeneous particles have effects similar to homogeneous particles of the same average refractive index. Thus most problems can be solved to a satisfactory approximation by reference to the exact solutions for spheres and cylinders, which are fully stated here in the early part of the book. The sum of scattering and absorption, the extinction, is too large to be explained by inorganic materials, provided element abundances in the interstellar medium are not appreciably greater than solar, H 0 and NH3 being essentially excluded in the 2 general medium, otherwise very strong absorptions near 3p, m would be observed which they are not. A well-marked extinction maximum in the ultraviolet near 2200A has also not been explained satisfactorily by inorganic materials. Accurately formed graphite spheres with radii close to O.02p, m could conceivably provide an explanation of this ultraviolet feature but no convincing laboratory preparation of such spheres has ever been achieve

These proceedings are the result of a three-day meeting held in Oogliani (Italy), on October 2-4 2003, whose title was "VIrtual Astrophysical Jets 2003". Our goal in convening this meeting was to gather some of the scientists among the most active in the field of numerical simulations and modelling of astrophysi cal jets. For keeping the participants close to the "real world", we also invited a few observers to give up-to-date reviews outlining the state-of-the-art of jet observations. The principal aim of the meeting was thus to present and critically discuss the state-of-the-art numerical simulations, analytical models and laboratory ex periments for reproducing the main aspects of astrophysical jets and compar ing them with observations. The discussion has been focused on the following topics: * Observations and intepretions of jets from young stars and AGNs, comparisons of models with observations; * MHO accelerations of jets: steady self-similar models, MHO numerical simula tions of time-dependent accelerations mechanisms; * Jet stability and interaction with the ambient: formation of knots in YSO jets, jet survival to instabilities, deceleration of relativistic jets in FRI sources, simulations of jets-IGM interactions, jets propagation and galaxy formation; * Numerical codes and their validation: relativistic MHO codes, comparisons among different numerical schemes, jets in the laboratory and code validation. These topics have been discussed intensively during the meeting, and the out come of these discussions is presented in this volume. The contributions have been divided in five sections.

The General Assemblies of the International Astronomical Union are landmarks in the life of the world-wide astronomical community, as they review, at triennial intervals, the progress made in this scientific field, promulgate the most spect acular astronomical achievements, formulate scientific programmes for the years to come and, last but not least, deal with the administration and finances of the IAU. The Reports on Astronomy 1976, published as Transactions XVIA (in 3 volumes) before the XVlth General Assembly, are a synopsis of the work done in astronomy from 1973 to 1975. The volume "Highlights of Astronomy, as presented at the XVlth General As sembly of the IAU in Grenoble, 1976" includes some selected scientific topics, and will appear in the first half of 1977. Apart from the Invited Discourses and the Proceedings of the seven Joint Discussions, the Highlights volume No.4 con tairsthe proceedings of two Joint Commissions Meetings."

IAU Transactions are published as a volume corresponding to each General Assembly. Volume A is produced prior to the Assembly and contains Reports on Astronomy, prepared by each Commission President. The intention is to summarize the astronomical results that have affected the work of the Commission since the production of the previous Reports up to a time which is about one year prior to the General Assembly. Volume B is produced after the Assembly and contains accounts of Commission Meetings which were held, together with other material. The reports included in the present volume range from outline summaries to lengthy compilations and references. Most reports are in English.

The 2nd International Conference on Space Engineering took place May 7-10, 1969, at Venice, Italy, under the organization of the Centro Studi Trasporti Missilistici and the Association pour l'Etude et la Recherche Astronautique et Cosmique. Its purpose was to bring together those interested in the technological development of space components, to exchange information by the presentation of papers and to discuss present problems and future trends, and to this end forty-eight papers were presented by distinguished experts from all over the world. The papers were selected from as wide a background as possible, approximately an equal number coming from the academic and research establishments as from industry. The principal criterion for their selection was that they should contribute to the knowledge of Space Engineering, and have application either to the improve ment of current technologies or to the design of more advanced systems for the future. Six pertinent sessions were planned which covered the major areas of interest: (1) Structures and Materials, where three important papers were presented; (2) Guidance and Control Systems, in which six valuable papers were presented, in cluding problems of controlling space ships, details of the inertial guidance system of the ELDO launch vehicle, the attitude control system of the "Europa 2"; (3) Propellants and Combustion, where eleven papers described recent work on solid and liquid rocket engines, advanced fuels and oxidizers, effects of additives, propellant injection, propellant expulsion techniques; (4) Propulsion, in which session ten papers"

decision and investigative process of the scientist, they can also wri te the paragra}ils of scientific resul ts. Once a canputer research activity progresses from intuitive guesses to a systematic study, the canputer program can free the scientist to pursue new original ideas. '!his concept is illustrated in the ptper by Hut. Sussnan says "Knowledge" is knowing what not to canpute. His main message is that we must change from trying to maximize the efficiency of the canputer to maximizing the effectiveness of the scientist. The canputer is relatively cheap, it is the trained scientist who is most valuable. In the second keynote address, R. L. Duncombe (University of Texas) described the "Early Applications of Canputer Technology to Dynamical Astronany. " His talk traced the worldwide introduction of punched card equipnent and their applications through the use of the first electronic canputers. Sussman and Duncombe, therefore, provided a forecast and review of the use of computers in dynamical astronany. This proceedings is intended to provide a consolidated general view of the ptst, present, and future of the Applications of Canputer Technology to Dynamical Astronany. Of necessity this requires that the ptpers be rela ti vely short and provide references to the more canplete discussions. Thanks to the representa tion from so many different countries the proceedings give a picture of the activities worldwide. The Scientific Organizing Comnittee included K. B. IIlatnagar, V. A. Brtmberg, G. Contopoulos, A. Depri t , J. Henrard, J. Kovalevsky, Y.

In their approach to Earth dynamics the authors consider the fundamentals of "Jacobi Dynamics" (1987, Reidel) for two reasons. First, because satellite observations have proved that the Earth does not stay in hydrostatic equilibrium, which is the physical basis of today's treatment of geodynamics. And secondly, because satellite data have revealed a relationship between gravitational moments and the potential of the Earth's outer force field (potential energy), which is the basis of "Jacobi Dynamics." This has also enabled the authors to come back to the derivation of the classical virial theorem and, after introducing the volumetric forces and moments, to obtain a generalized virial theorem in the form of Jacobi's equation. Thus a physical explanation and rigorous solution was found for the famous Jacobi's equation, where the measure of the matter interaction is the energy.
The main dynamical effects which become understandable by that solution can be summarized as follows:
" "the kinetic energy of oscillation of the interacting particles which explains the physical meaning and nature of the gravitation forces;
" "separation of the shell's rotation of a self-gravitating body with respect to the mass density;
difference in angular velocities of the shell rotation;
" "continuity in changing the potential of the outer gravitational force field together withchanges in density distributionof the interacting masses (volumetric center of masses);
" "the nature of the precession of the Earth, the Moon and satellites; the nature of the rotating body's magnetic field and the generation of the planet's electromagnetic field.As a final result, the creation of the bodies in the Solar System having different orbits was discussed. This result is based on the discovery that all the averaged orbital velocities of the bodies in the Solar System and the Sun itself are equal to the first cosmic velocities of their proto-parents during the evolution of their redistributed mass density.
Audience
The work is a logical continuation of the book "Jacobi Dynamics" and is intended for researchers, teachers and students engaged in theoretical and experimental research in various branches of astronomy (astrophysics, celestial mechanics and stellar dynamics and radiophysics), geophysics (physics and dynamics of the Earth's body, atmosphere and oceans), planetology and cosmogony, and for students of celestial, statistical, quantum and relativistic mechanics and hydrodynamics.

The second workshop on High Energy Astrophysics of the Ma..x-Planck-Society and the Academia Sinica was held at Ringberg Castle near Tegernsee during the week July 12-July 17, 1987. It is the purpose of these workshops to en courage the exchange of ideas between German and Chinese astrophysicists (scientists from other countries are also welcome, of course), and the pleas ant atmosphere and surroundings of Ringberg Castle certainly helped the development of relaxed and stimulating discussions. In addition, we seemed to have picked out the one week of perfect weather during a rainy summer. Thanks are due to Mr. Hormann and his staff for creating a perfect infra structure. The proceedings have required a considerable amount of editing, and I hope that all the papers are comprehensible. Thanks are due to Miss Petra Berkemeyer and Miss Hannelore Muller, who patiently retyped several manu scripts and helped with other editing jobs. I did not feel that a sharp refer eeing procedure should be done, although I do not agree with all the papers in this volume. The interested reader will find that this book gives a fair account of the present status of Chinese activities in the field of high energy astrophysics, i.e. in supernova physics, accretion onto compact objects, active galaxies, and cosmology."

In the 18th century, purely scientific interests as well as the practical necessities of navigation motivated the development of new theories and techniques to accurately describe celestial and lunar motion. "Between Theory and Observations" presents a detailed and accurate account, not to be found elsewhere in the literature, of Tobias Mayer's important contributions to the study of lunar motion-including the creation of his famous set of lunar tables, which were the most accurate of their time.

Optics is reborn. There is fresh new vitality in applying old techniques to new prob lems and fully exploring novel phenomena. Lasers, holography, stellar navigation, nonlinear phenomena, and remote sensing are subjects of the seventies, and their further development will increase our understanding of nature and the development of technology. This Series is devoted to provid ing ideas and data to nourish the growth of these scientific and engineering en deavors' for we feel strongly that science and engineering flourish best when they grow together. Some of the volumes in the Series will be devoted to the optical properties of materials, theories of the detailed mechanisms of absorption, reflection, and nonlinea r phenomena, and electro-optical coefficients. The understanding of such things leads to further engineering applications. Companions to such theoretical books will be compendia of property data; the triad is completed by monographs on the use of the materials in op tical and electro-optical systems. Laser materials, lasers, and laser sys tems form one of the groups which will comprise the full set of ready-reference material for the entire field. The Series will be intentionally international, including a fair sampling of Russian work. There are important benefits to be obtained in the alternate approaches often taken by our Soviet and other foreign colleagues (just as they can gain from studying ours)."

The Cargese Workshop Random Surfaces and Quantum Gravity was held from May 27 to June 2, 1990. Little was known about string theory in the non-perturbative regime before Oetober 1989 when non-perturbative equations for the string partition functions were found by using methods based on the random triangulations of surfaees. This set of methods pro vides a deseription of non-eritical string theory or equivalently of the coupling of matter fields to quantum gravity in two dimensions. The Cargese meeting was very successful in that it provided the first opportunity to gather most of the active workers in the field for a fuH week of lectures and extensive informal discussions about these exeiting new developments. The main results were reviewed, recent advances were explained, new results and conjectures (which appear for the first time in these proceedings) were presented and discussed. Among the most important topics discussed at the workshop were: The relation of KdV theory to loop equations and the Virasoro algebra, new results in Liouville field theory, effective (1 + 1) dimensional theory for 2 - D quantum gravity coupled to c = 1 matter and its fermionization, proposal for a new geometrical interpretation of the string equation and possible definition of quantum Riemann surfaces, discussion of the string equation for the multi-matrix models, links with topological field theories of gravity, issues in using target space supersymmetry to define good theories, definition of the partition function via analytic continuation, new models of random surfaces

Modern astronomical research faces a vast range of statistical issues which have spawned a revival in methodological activity among astronomers. The Statistical Challenges in Modern Astronomy II conference brought astronomers and statisticians together to discuss methodological issues of common interest. Time series analysis, image analysis, Bayesian methods, Poisson processes, nonlinear regression, maximum likelihood, multivariate classification, and wavelet and multiscale analyses were all important themes. Many problems were introduced at the conference in the context of large-scale astronomical projects including LIGO, AXAF, XTE, Hipparcos, and digitised sky surveys. As such, this volume will be of interest to researchers and advanced students in both fields - astronomers seeking exposure to recent developments in statistics, and statisticians interested in confronting new problems.