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.

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."

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.

This book is one result from the 1996 Millimeter-wave Summer School held at the Instituto Nacional de Astrofisica, Optica y Electronica (INAOE), Tonantz- intla, Puebla, Mexico. In collaboration with the University of Massachusetts, INAOE has embarked upon the ambitious project of building the world's largest filled aperture millimeter-wave telescope - the Large Millimeter-wave Tele- scope (LMT), or Gran Telescopio Milimetrico (GTM). The LMT is currently the largest scientific project in Mexico. The summer school had a dual purpose; first, to introduce the Mexican as- tronomical and physics communities to millimeter wavelength astronomy, and second, to provide a forum for a review of several important aspects of the state of the art in observations, theory, interpretation, and technology relevant to this branch of astronomy. The summer school had 18 invited speakers and 44 par- ticipants. The scientific organizing committee (SOC) consisted of Luis Carrasco (UNAM/INAOE, Mexico), Paul Goldsmith (NAIC, Cornell Univ., USA), and Andy Harris (Univ. of Maryland, USA). Members of the local organizing com- mittee (LOC) were Alberto Carramiiiana (INAOE), Emmanuel Mendez Palma (INAOE), Mari Paz Miralles (Harvard-Smithsonian Center for Astrophysics, USA), and William Wall (INAOE).

Radio surveys play an important role in observational cosmology. However, until recently the surveys have been either of wide area but with low sensitivity or of small area with high sensitivity. Both limit the kinds of cosmology that can be carried out with radio surveys. This situation has been revolutionised in the past few years by the availability of new, large-area, high-sensitivity radio surveys at both low and high radio frequencies. These significant improvements allow studies based on both the statistics of the surveys themselves and multiwavelength follow-up of the galaxies and AGN responsible for the radio emission. It is therefore an opportune time to summarise progress in this field with a workshop. This book comprises the proceedings of the `Observational Cosmology with the New Radio Surveys' workshop, held on Tenerife, January 13-15, 1997. Topics covered include: lessons learned and important results from earlier surveys, descriptions of some of the new surveys, clusters of galaxies and large-scale structure, radio source evolution, CMB studies, gravitational lensing and multiwavelength studies of distant radio sources.

The Galactic cosmic rays have far-reaching effects on the interstellar medium, and they are, in turn, profoundly affected by the particles and fields in space. Supernova remnants and their expanding shock fronts pervade the Galaxy, heating the interstellar medium, and accelerating the cosmic rays. The interplay among the cosmic rays, the interstellar medium in which they propagate, and supernovae has been investigated for decades; yet these studies have generated as many enigmas as they have resolved. These puzzles continue to challenge observers and theorists alike. th This volume is devoted to selected lectures presented in the 7 Course of the International School of Cosmic-Ray Astrophysics in Erice, Italy in July-August, 1990. Alltogether, some 400 participants have attended the biennial sessions of this School since its inception in 1978. As its name implies, the School deals with cosmic-ray phenomena viewed in the broader context of astrophysics. Students and Lecturers are attracted from many astrophysical disciplines. Like earlier courses in this series, the present one was organized under the aegis of the Ettore Majorana Centre as a NATO Advanced Study Institute. Given the diverse scientific backgrounds of the students, it was deemed useful to include lectures at the introductory level. Other lectures and contributed talks were at a more advanced level, featuring new developments. If this collection is useful pedagogically, and if it provides some stimulus and information for the mature research worker, then the editors will feel well rewarded.

This five-year project started on 25th September 1986. Eventually, sixteen countries and the European Commission itself signed the Memorandum of Understanding. The principal objectives of the Project were to further the establishment of national operational weather radar networks, harmonise operations, data handling and processing to minimise the difficulties of, and maximise the benefits of international weather radar data exchange. To transmit the data efficiently, standardised formats and protocols were essential. These were formulated by a working group whose efforts were rewarded when WMO accepted their proposal for worldwide use. A multi-national pilot project area was established and streams of data from each of the countries involved were merged and integrated with data from the satellite METEOSAT. The composite image, known as the COST image' was regularly distributed via the global telecommunication system of WMO, the public telephone switched network and the Olympus satellite. The utility of the COST image was assessed for, inter alia, short-period forecasting, aviation flight assistance, maritime forecasting and the initialisation of numerical weather prediction models. In all cases, the COST image was found to be beneficial. A report containing proposed curricula for the training of meteorologists, hydrologists and other major users of weather radar data was sent to WMO for possible adoption as one of their standard training manuals. As a report of international scientific cooperation, this is a success story. All the principal objectives of the Memorandum of Understanding were achieved both within time and budget. It is a tale of international cooperation at its best.

International Weather Radar Networking covers all aspects of the subject in a collection of contributions drawn from all over the world. Of particular interest are the papers describing work in Eastern Europe and papers reviewing of the achievements of the Commission of the European Communities COST-73 project. During the last twenty years there has been a rapid growth in the number of digital radars deployed for operational use in Western Europe. There are now around 100, of which about half have a Doppler capability, providing wind as well as reflectivity information. The international exchange of the data from these systems promises a great enhancement of the benefits to weather forecasting and commercial users. This volume reports work being undertaken to realize those benefits and points the way to future developments of radar technology.

This unique volume contains the proceedings of two "Non-Sleeping Universe" conferences: "Stars and the ISM" and "From Galaxies to the Horizon." The book provides an overview of recent developments in a variety of areas, covering a very wide range of spatial and temporal scales.

Between 1920 and 1960 astronomers began working with scientists in other fields in order to better understand the nature of the solar system. Researchers made wide-ranging attempts to solve such problems as the nature of lunar and terrestrial craters, the origin of comets and meteors, and the birth of the solar system. While often tinged with controversy, this work provided the foundation for planetary science in the space age. Exploiting previously unused archival material, Ronald Doel investigates this emerging interdisciplinary scientific community and its influence on astronomy, meteorology, geology, and geophysics. He examines how studies in planetary science were influenced by shifts in institutional mandates, new research techniques, and Cold War government-military funding. Above all, the book explores an important branch of what is now called the environmental sciences. This book will interest historians of science as well as astronomers.

More than two centuries have elapsed since the story of the interacting binary stars began with the rediscovery of the variability of Algol by John Goodricke and the interpretation he proposed for explaining the regular periodic brightness variations which he found. Over this long span of time our knowledge about these systems has been growing, and we have now reached a fairly good understanding of the structure and behavior of this interesting group of objects. This book contains a timely summary of our present knowledge of interacting binary stars. The chapters have been written by distinguished scientists who have done relevant research in the field of interacting binary stars.

A wealth of new experimental and theoretical results has been obtained in solar physics since the first edition of this textbook appeared in 1989. Thus all nine chapters have been thoroughly revised, and about 100 pages and many new illustrations have been added to the text. The additions include element diffusion in the solar interior, the recent neutrino experiments, methods of image restoration, observational devices used for spectroscopy and polarimetry, and new developments in helioseismology and numerical simulation. The book takes particular advantage of the results of several recent space missions, which lead to substantial progress in our understanding of the Sun, from the deep interior to the corona and solar wind.

In the last few years great improvements in the study of stellar jets and bipolar outflows have been achieved, both observationally and theoretically. High resolution observations at various frequencies (radio, IR, optical and X-ray) of these features in different types of objects have shown a large variety of morphologies at all scales often revealing contrasting symmetries which do not allow straightforward kinematic interpretations valid for all cases. In particular, at present, it seems very difficult to give a statistical definition of what the "standard properties" of jets and bipolar outflows are. On the theoretical side, the identification of physical processes capable of producing the observed rich morphological variety of jets and bipolar outflows and supporting them over long lifetimes is still controversial. Furthermore several models are actively discussed in an attempt of reaching a complete understanding of the phenomenon. The workshop provided an unique opportunity for both observers and theoreticians to gather together and produce an updated and exhaustive picture of the field. In addition the meeting has been enriched by the presentation of some works on jets in external galaxies. This topic was focused on what people working on stellar jets could learn from colleagues working on extragalactic jets and vice versa. Invited papers were prepared with the aim of giving the state of the art about scientific subjects; contributed papers and some selected poster papers presented, on the contrary, very recent results in the various fields.

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.

The articles in this book cover a broad range of topics in the field of nuclear physics, including many articles on the subject of high spin physics. With an emphasis on the discussion and analysis of future developments within a number of significant areas, the book's attempt to address the status of research at the beginning of the next century is to be welcomed by researchers and students alike.

The morphological scheme devised by Hubble and followers to classify galaxies has proven over many decades to be quite effective in directing our quest for the fundamental pa rameters describing the extragalactic manifold. This statement is however far more true for spirals than for ellipticals. Echoing the concluding remarks in Scott Tremaine's sum mary talk at the Princeton meeting on Structure and Dynamics of Elliptical Galaxies, "the Hubble classification of spirals is useful because many properties of spirals (gas con tent, spiral arm morphology, bulge prominence, etc. ) all correlate with Hubble time. By contrast, almost nothing correlates with the elliptical Hubble sequence El to E7. " During the last few years much effort has been put into the search for a more meaningful classification of ellipticals than Hubble's. Concomitantly, forwarded by some provocative conjectures by R. Michard, the classical question of whether E galaxies form a physically homogeneous family has been brushed up once more. Results of these and other parallel studies look rather promising and point to suture part of the dichotomy between ellipticals and disk galaxies which had become popular in the early eighties, owing to dynamical arguments. At the same time it appears more and more clear that, besides the usual genetic varieties of galaxies, products of environmental evolution must also be contemplated in building our modern picture of the "reign of galaxies" . The above considerations prompted us to solicit Prof."

Solid particles are followed from their creation through their evolution in the Galaxy to their participation in the formation of solar systems like our own, these being now clearly deduced from observations by the Hubble Space Telescope as well as by IR and visual observations of protostellar disks, like that of the famous Beta Pictoris object. The most recent observational, laboratory and theoretical methods are examined in detail. In our own solar system, studies of meteorites, comets and comet dust reveal many features that follow directly from the interstellar dust from which they formed. The properties of interstellar dust provide possible keys to its origin in comets and asteroids and its ultimate origin in the early solar system. But this is a continuing story: what happens to the solid particles in space after they emerge from stellar sources has important scientific consequences since it ultimately bears on our own origins - the origins of solar systems and, especially, of our own earth and life in the universe.

The conference recorded in this volume was one of the events organised to celebrate the centenary of the (re)establishment of the Royal Observatory, Edinburgh, on Blackford Hill in 1884. Circumstellar Matter was selected as the topic because of important contributions toward research in the field by recent observations in the infrared and submillimetre, particularly with the two telescopes which the Observatory has both operated and built instru mentation for - the United Kingdom Infrared Telescope (UKIRT) and the James Clerk Maxwell Telescope (JCMT). The programme aimed to cover as many aspects of circumstellar matter as could fit into a one-week meeting, omitting only planetary nebulae, which had been well served by meetings in the previous two years. We thank the international scientific advisory com mittee (overleaf) for their help in selecting the Invited Reviewers around which the programme was built. The Invited Reviews and oral contributions are included in the order and sections in which they were presented, even where re-ordering might have been more logical. We did not attempt to categorise the poster contributions but have included them in alphabetical order. An evening session for viewing and discussing posters in an unhurried atmosphere was very successful. A competition for the best poster was held and the prize was awarded for that by Lindqvist, Lucas, Olofsson, Omont, Eriksson & Gustafsson."

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.

An almost complete collection of the papers given at the International Workshop on Imaging in High Energy Astronomy (Anacapri, Italy, 1994). These proceedings, which concentrate on imaging above 10 keV, represent the state of the art in the field, resulting from the success of many missions (I.C. Granat and CGRO) carrying detectors for high energy astronomy with imaging capabilities. The main topics of the book are Bragg concentrators, coded mask-modulation collimators, double Compton telescopes, the occultation method, tracking chambers, and new experimental techniques. The book also contains some papers dealing with image reconstruction and processing, with an emphasis on the above techniques.

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.

Prof. Leon Mestel has been an inspiration to many to study the role of magnetism in the Cosmos. To mark the occasion of his retin'ment from the University of Sussex after 43 years in astrophysics, several of his friends and former students decided to hold an advanced research workshop in his honour. NATO agreed to finance this venture which was held at the Institute of Astronomy at Cambridge. The scientific organizing committee was J. Landstreet, D. Lynden-Bell, F. Pacini, M.A. Rud0rman and N.O. Weiss and most leading experts on Cosmical magnetism agreed to come. We are particularly grateful to Lyman Spitzer who, ably helped by his wife Doreen, !!;ave the after dinner addre~s on how the goddess Astrophysica had foreseen Leon's achievements in classical Greek times. Not without regret we decided to maintain the homog0neity of the material and therefore could not cover Leon Mestel's major achievements in non-magnetic astronomy. His work on the cooling of white dwarfs, his understanding that degenerate hydrogen was a nuclear explosive since its pressure was almost independent of temperature and hence, his picture of supernovae, which is now more commonly applied to novae, his seminal understanding of the 'law' of galactic rotation and his work on the non-linear development of t hp anisotropies generated in gravitational collapse.

Interstellar dust, meteorites, interplanetary dust particles (IDP's), the zodiacal light, comets, comet dust. Where do they come from, what are they made of, how do they evolve, and finally, are there connections between them? These are the questions discussed in this volume by some of the world's outstanding experts in their respective fields. The techniques used for studying the `small' solid objects of space are thoroughly discussed. Some of the methods involve a synthetic approach using the laboratory to create analog environments and materials which are believed to resemble those in space. Others use direct laboratory methods with state-of-the-art analytical tools to study the material of the objects themselves - meteorites, IDP'S. And others apply the latest in astronomical facilities to provide quantitative data on the material properties of the solids which can only be deduced from remote observations, These are compared with the laboratory results. In one instance there was a possibility to study a solar system body in situ and that was the case of comet Halley and some of the results of these studies obtained from space `laboratories' launched to meet it are discussed here. Finally, there are theoretical papers which are aimed at bridging the results of observational and laboratory methods. This book is recommended to senior scientists as well as graduate students who wish to pursue research in interstellar and solar system astronomy and their connections.

The last decade has been witness to many exciting and rapid developments in the fields of Nuclear Physics and Intermediate Energy Physics, the interface between Nuclear and Elementary Particle Physics. These developments involved to a large extent the sub nucleonic degrees of freedom in nuclei. In deep inelastic lepton scattering from nuclei, for example, it was observed that the quark structure of the nucleon is influenced by the nuclear medium. Also, the spin-dependent structure function of the nucleon was found to differ from sum rules based on SU(3) symmetry, a discrepancy referred to as the "spin crisis". In pion electroproduction at threshold and in the production of pions and other mesons in heavy ion collisions at intermediate energies interesting experimental results have been obtained, which triggered lively theoretical discussions. Furthermore, the search for the quark-gluon plasma phase of hadronic matter, a phase that is supposed to have existed in the first few seconds of the Big Bang, has been intensified. Not only were these developments accompanied by technical developments, such as the building of new experimental facilities, but also extensive theoretical efforts have been directed towards understanding these phenomena. These concerted efforts will hopefully lead to an understanding of the transition from the non-perturbative QCD regime to the perturbative one, in which the quark structure of nucleons is better understood. All of the aforementioned developments occur at a high pace, making it difficult to incorporate them into the courses offered to advanced students.

Once you have looked at the night sky on a moonless night it is not hard to realise why so much of our science and religion has its roots in the stars. Yet it took until 1850 to realise that fainter stars were not necessarily further away, nor the brighter ones closer. In fact within the magnitude range observable to the naked eye it is probable that the brighter star is in fact further away. Even today the measurement of stellar distances is relatively difficult and is gener ally only done using dedicated telescopes. In the early years of the 20th century Hertzsprung and Russell developed a powerful classification diagram which al lows stars to be distinguished using a plot of their colour versus magnitude. The construction of this diagram involved the use of spectroscopy which has become the cornerstone of modern astronomy. As telescopes become more powerful, de tectors more sensitive and more physics is added to astrophysics, astronomical spectroscopy becomes a more powerful tool. The concern of this book is the spectral classification of stars. With a single spectrum of a star it is possible to uniquely classify an object and find its place on the Hertzsprung-Russell diagram. This spectrum is thus equivalent to having the colour and the magnitude of the object which can in turn be related to mass and other quantities."