The scientific meetings of the !AU are the !AU Symposia, !AU Colloquia, Regional Meetings in Astronomy held under the auspices of the !AU, the Commission Meetings, which may be Joint Meetings of Commissions, and !AU Joint Discussions. This variety means that almost any demand for a meeting can be provided for by the !AU structure, pro vided it is international in character, whatever may be the preferences of the proposers. The !AU General Assemblies include Co~ssion Meetings and Joint Discussions arranged by Commissions, together with the Invited Discourses, and it is these meetings that feature in this volume. The administrative work of the General Assembly is reported in the Transactions of the !AU and the Proceedings of the !AU Symposia, held in the host country or neighbouring countries during the year of a General Assembly, appear in the !AU Symposium Volume series. !AU Collo quium volumes are published separately. The Invited Discourses are a popular feature of the !AU General Assemblies and each of the three discourses presented at the XVIIth General Assembly in Montreal in 1979 appear in this volume. 1979 was the Centenary Year of the birth of Albert Einstein and the occasion was marked, for the !AU, by a discourse of great distinction from Professor S. Chandrasekhar of the University of Chicago, whose contri butions to astrophysics themselves cover fully a half-century. The Invited Discourse by G. Herzberg of the National Research Council of Canada, a Nobel Prizewinner, was equally notable as an !AU occasion.

Taking both a theoretical and observational perspective, this book is an introduction to recent developments in the field of celestial mechanics. It emphasizes the application to extended celestial bodies and devotes much attention to rotational aspects. In particular, it explains the state of art for accurate modelling of the rotation of celestial bodies such as the Earth, the Moon, and Mercury, which involves principles related to hydrodynamics and geodesy. Comparisons between the light curves of the asteroids and their rotational state are made and spatial techniques leading to the determination of the Earth's gravitational field are explained. Also, the book provides a general overview of the collisional processes in the solar system and of the dynamics of the rings. It is addressed to graduate students and researchers in space sciences and celestial dynamics.

Astronomy on the Personal Computer provides the reader with a thorough introduction to the computation of celestial mechanics, which is of particular significance to astronomical observation. Covering everything from astronomical and computational theory to the construction of rapid and accurate applications programs, this book supplies the necessary knowledge and software solutions for determining and predicting the positions of the Sun, Moon, planets, minor planets and comets, solar eclipses, stellar occultations by the Moon, phases of the Moon and much more. This completely revised edition makes use of the widely implemented programming language C++, and individual applications may be efficiently realized through the use of a powerful module library. The accompanying CD-ROM contains, in addition to the complete, fully documented and commented source codes, the executable programs for use with the Windows 95/98/NT and Linux operating systems.

Describing interstellar matter in our galaxy in all of its various forms, this book also considers the physical and chemical processes that are occurring within this matter. The first seven chapters present the various components making up the interstellar matter and detail the ways that we are able to study them. The following seven chapters are devoted to the physical, chemical and dynamical processes that control the behaviour of interstellar matter. These include the instabilities and cloud collapse processes that lead to the formation of stars. The last chapter summarizes the transformations that can occur between the different phases of the interstellar medium. Emphasizing methods over results, The Interstellar Medium is written for graduate students, for young astronomers, and also for any researchers who have developed an interest in the interstellar medium.

Dwarf galaxy research constitutes an extremely vibrant field of astrophysical research, with many long-standing questions still unsettled and new ones constantly arising. The intriguing diversity of the dwarf galaxy population, observed with advanced ground-based and space-borne observatories over a wide spectral window providing an unprecedented level of detail, poses new challenges for both observers and theoreticians.
The aim of this symposium was to bring together these two groups to exchange ideas and new results on the many evolutionary aspects of and open issues concerning dwarf galaxies. The main topics addressed include: the birth of dwarf galaxies: theoretical concepts and observable relics across wavelengths and time, the morphological, structural and chemical evolution of dwarf galaxies, possible evolutionary connections between early-type and late-type dwarfs, the star formation history of dwarf galaxies and its dependence on intrinsic and environmental properties, the origin and implications of starburst activity in dwarf galaxies, the fate of dwarfish systems born out of tidally ejected matter in galaxy collisions.

This book contains a selection of refereed papers presented at the 6 Specialist Meeting on Microwave Radiometry and Remote Sensing of the Environment held in Florence, Italy on March 15-18, 1999.
Over the last two decades, passive microwave remote sensing has made considerable progress, and has achieved significant results in the study of the Earth's surface and atmosphere. Many years of observations with ground-based and satellite-borne sensors have made an important contribution to improving our knowledge of many geophysical processes of the Earth's environment and of global changes. The evolution in microwave radiometers aboard satellites has increased steadily over recent years. At the same time, many investigations have been carried out both to improve the algorithms for the retrieval of geophysical parameters and to develop new technologies.
The book is divided into four main sections: three of these are devoted to the observation of the Earth's surface and atmosphere, and the fourth, to future missions and new technologies. The first section deals with the study of sea and land surfaces, and reports recent advances in remote sensing of ocean wind, sea ice, soil moisture and vegetation biomass, including electromagnetic modelling and the assimilation of radiometric data in models of land surface processes. The following two sections are devoted to the measurement of atmospheric quantities which are of fundamental importance in climatology and meteorology, and, since they influence radio-wave propagation, they also impact on several other fields, including geodesy, navigational satellite and radioastronomy. The last section presents an overview of new technologies and plansfor future missions.

There has been very considerable progress in research into low-mass stars, brown dwarfs and extrasolar planets during the past few years, particularly since the fist edtion of this book was published in 2000. In this new edtion the authors present a comprehensive review of both the astrophysical nature of individual red dwarf and brown dwarf stars and their collective statistical properties as an important Galactic stellar population. Chapters dealing with the observational properies of low-mass dwarfs, the stellar mass function and extrasolar planets have been completely revised. Other chapters have been significantly revised and updated as appropriate, including important new material on observational techniques, stellar acivity, the Galactic halo and field star surveys. The authors detail the many discoveries of new brown dwarfs and extrasolar planets made since publication of the first edition of the book and provide a state-of-the-art review of our current knowledge of very low-mass stars, brown dwarfs and extrasolar planets, including both the latest observational results and theoretical work.

Routledge is now re-issuing this prestigious series of 204 volumes originally published between 1910 and 1965. The titles include works by key figures such asC.G. Jung, Sigmund Freud, Jean Piaget, Otto Rank, James Hillman, Erich Fromm, Karen Horney and Susan Isaacs. Each volume is available on its own, as part of a themed mini-set, or as part of a specially-priced 204-volume set. A brochure listing each title in the "International Library of Psychology" series is available upon request.

The Alfonsine Tables became the main computing tool for astronomers for about 250 years, from their compilation in Toledo ca. 1272 to the edition in 1551 of new tables based on Copernicus s astronomical models. It consisted of a set of astronomical tables which, over time, was presented in many different formats. Giovanni Bianchini (d. after 1469), an astronomer active in Ferrara, Italy, was among the few scholars of that extended period to compile a coherent and insightful set based on the Alfonsine Tables. His tables, described and analyzed here for the first time, played a remarkable role in the transmission of the Alfonsine Tables and in their transition from manuscript to print. "Medieval and Early Modern Science," 10

Edgard Gunzig and Pasquale Nardone RGGR Universite Libre de Bruxelles CP231 1050 Bruxelles Belgium The NATO Advanced Research Workshop on "The Origin of Structure in the Universe" was organized to bring together workers in various aspects of relativistic cosmology with the aim of assessing the present status of our knowledge on the formation and evolution of structure. As it happened, the meeting was particularly timely. Only two days before the 30 or so physicists from many countries gathered for a week at the Chateau du Pont d'Oye, in the forests of the southern Belgian province of Luxembourg, newspaper headlines all over the world announced the results of the analysis of the first full year of data from the Cosmic Background Observer Satellite (COBE). This long-awaited confirmation of the theoretically predicted anisotropy in the microwave background radiation opened a new era in observational cos mology. The realization of the new relevance of the subject of the workshop and the questions raised by the observational results, in addition to bring ing TV crews and newspaper journalists, naturally influenced and stimulated many discussions among the participants. The success of the meeting as usual is due to a combination of factors. Besides the high quality of the talks, discussions were encouraged by the warm atmosphere of the Chateau, for which we are grateful to Mme. Camille Orts, and its beautiful surroundings, not to mention the marvelous cuisine."

Growing evidence, based on observations from orbiters, landers and telescopes, indicates that Mars may still have numerous hidden water reservoirs. Moreover, from the point of view of habitability, Mars is a prime target for astrobiologists in search of extant or extinct microbial life because we know that life exists in eartha (TM)s permafrost regions, such as parts of Siberia and the Antarctic, which are the closest terrestrial analogues to Mars. Water on Mars and Life surveys recent advances made in research into water on Mars together with its astrobiological implications. This volume addresses not only scientists working in the field but also nonspecialists and students in search of a high-level but accessible introduction to this exciting field of research.

IX LIST OF PRINCIPAL SPEAKERS XI LIST OF PARTICIPANTS 1. REGULARIZATION E. STIEFEL / A Linear Theory of the Perturbed Two-Body Problem (Regul- ization) 3 J. WALDVOGEL / Collision Singularities in Gravitational Problems 21 D. C. HEGGIE / Regularization Using a Time-Transformation Only 34 J. BAUMGAR TE / Stabilization of the Differential Equations of Keplerian Motion 38 F. NAHON / The Particular Solutions of Levi-Civita 45 O. GODAR T / Example ofIntegration of Strongly Oscillating Systems 53 w. BLACK / The Application of Recurrence Relations to Special Perturbation Methods 61 D. G. BETTIS / Numerical Solution of Ordinary Differential Equations (Abstract) 71 II. THE THREE-BODY PROBLEM V. SZEBEHELY / Recent Advances in the Problem of Three Bodies 75 R. F. ARENSTORF / Periodic Elliptic Motion in the Problem of Three Bodies (Abstract) 107 G. KATSIARIS and c. L. GOUDAS / On a Conjecture by Poincare 109 G. KATSIARIS / The Three-Dimensional Elliptic Problem 118 P. G. KAZANTZIS / Second and Third Order Variations of the Three Dimensional Restricted Problem 135 c. G. ZAGOURAS / Planar Periodic Orbits Using Second and Third Variations 146 E. RABE / Elliptic Restricted Problem: Fourth-Order Stability Analysis of the Triangular Points 156 P. GUILLAUME / A Linear Description of the Second Species Solutions 161 III. THE N-BODY PROBLEM AND STELLAR DYNAMICS G. CONTOPOULOS / Problems of Stellar Dynamics 177 w. T. KYNER / Invariant Manifolds in Celestial Mechanics 192 s. J.

Sponsored by the Global Foundation, Inc., these proceedings are derived from the International Conference on Orbis Scientiae II. Topics covered include: gravitational mass, neutrino mass, particle masses, cosmological masses, susy masses, and big bang creation of mass.

NASA's Advanced Composition Explorer (ACE) was launched on August 25, 1997, carrying six high-resolution spectrometers that measure the abundances of the elements, isotopes, and ionic charge states of energetic nuclei in space. Data from these instruments is being used to measure and compare the composition of the solar corona, the nearby interstellar medium, and cosmic-ray sources in the Galaxy, and to study particle acceleration processes in a variety of environments. ACE also includes three instruments that monitor solar wind and energetic particle activity near the inner Lagrangian point, "1.5 million kilometers sunward of Earth, and provide continuous, real-time data to NOAA for use in forecasting space weather. Eleven of the articles in this volume review scientific progress and outline questions that ACE will address in solar, space-plasma, and cosmic-ray physics. Other articles describe the ACE spacecraft, the real-time solar-wind system, and the instruments used to measure energetic particle composition.

The Photographic Atlas of the Stars contains 50, high-quality full color photographs of the entire night sky of the northern and southern hemispheres. Each plate is accompanied by a star map of the identical area, which identifies the main stars of the constituent constellations as well as other interesting astronomical objects. In addition to this detail, Sir Patrick Moore has written a commentary for each plate that highlights the stars and objects of interest to observers equipped with binoculars and that includes detailed tabular information on astronomical objects of the region. The resulting double-page spread provides an invaluable reference for the amateur astronomer, detailing the constellations and other heavenly bodies of interest that are observable with the naked eye, binoculars, or a small telescope.

Black holes are becoming increasingly important in contemporary research in astrophysics, cosmology, theoretical physics, and mathematics. Indeed, they provoke some of the most fascinating questions in fundamental physics, which may lead to revolutions in scientific thought. Written by distinguished scientists, Classical and Quantum Black Holes provides a comprehensive panorama of black hole physics and mathematics from a modern point of view. The book begins with a general introduction, followed by five parts that cover several modern aspects of the subject, ranging from the observational and the experimental to the more theoretical and mathematical issues. The material is written at a level suitable for postgraduate students entering the field.

Proceedings of the 97th Colloquium of the International Astronomical Union, held in Brussels, Belgium, June 8-13, 1987

This book presents what are possibly the greatest advances in astronomy and physics for years. It quantifies the force responsible for the expansion of the universe and describes its source. It identifies the greatest destructive mechanism in the universe. The enigmas behind the Hubble constant were resolved and this led to all the discoveries. The mysteries behind dark matter and dark energy are solved. The cause of all solar energy, including gravitational and radiant energy is identified. Surprisingly hydrogen fusion is found to be responsible for the sun's remarkable prolonged stability, but it is an impossible source of surplus energy. The most unexpected finding was that time has an unusual property, one that is responsible for much of the behaviour of the universe. Also uncovered was an inverse relationship between time and mass. Another finding was the greatest catastrophe to befall the earth with after effects that we still feel today, such as shifting plate tectonics, tsunamis and earthquakes, and why the Pacific Ocean is so deep. That catastrophe led to Snowball Earth. But it also eventually caused the oxygenation of earth's atmosphere and the emergence of life. Also found were why Jupiter is so hot compared with its surroundings and what drives its equatorial storms. Another discovery was the mechanism responsible for Saturn's marvellous ring system. Also identified within that ring system was the physics behind the most spectacular sight in the solar system. But there are many other discoveries, such as that the theory of the Big Bang must be wrong, the quantification of gravitational energy and so on. This book should do to Astronomy what Darwin's book The Origin of Species did to biology.

Exciting results are blooming, thanks to a convergence between unprecedented asteroseismic data obtained by the satellites CoRoT and KEPLER, and state-of-the-art models of the internal structure of red giants and of galactic evolution. The pulsation properties now available for thousands of red giants promise to add valuable and independent constraints to current models of structure and evolution of our galaxy. Such a close connection between these domains opens a new very promising gate in our understanding of stars and galaxies. In this book international leaders in the field offer a wide perspective of the recent advancements in: Asteroseismology of red giants Models of the atmosphere, internal structure, and evolution of red giants Stellar population synthesis and models of the Milky Way

Our understanding of galaxy formation comes mostly from two sources: sensitive observations at high angular resolution of the high-redshift Universe, where galaxies are observed to be forming, and detailed observations of individual stars and clouds in the Local Group, where telltale remnants from its formative time remain and similar processes operate at a low level today. The current conference focusses on key aspects of the Local Group, composed of the Milky Way, Andromeda and Triangulum Spiral Galaxies, the Large and Small Magellanic Cloud galaxies, numerous dwarf and irregular galaxies, and intergalactic gas. Topics include the halo and thick disk of the Milky Way with its first stars and stellar streams; the Milky Way bar, bulge and outer edge; interstellar dust and turbulence; star formation processes and stellar scattering in spiral arms; views through the infrared Eyes of the Spitzer Space Telescope; globular clusters; the Local Gould Belt; stellar metallicities and elemental abundances; the environment and black hole in the Milky Way nucleus; orbits of the Magellanic Clouds and galaxy dwarfs; interstellar dust and turbulence; the outer disks and halos of the Andromeda and Triangulum galaxies; ripples from a collision in Andromeda; and arcs of carbon stars in the Triangulum and intergalactic clouds. This volume also discusses surveys of planetary nebulae, galaxy morphology at low and high redshift, cosmic evolution of star and galaxy formation and gas accretion, Lyman alpha emitting galaxies, ultra-low surface brightness imaging, and more. Readers are given a clear and comprehensive view of this wide range of topics written by specialists in each field. This is the proceedings of an International Conference at the Seychelles archipelago in May 2014, on the occasion of the 60th birthday of David Block and the millionth (base two) birthday of Bruce Elmegreen.

The SOHO-7 Workshop was held from 28 September through 1 October 1998 at the Asticou Inn in Northeast Harbor, Maine. The primary topic of this Workshop was the impact of SOHO observations on our understanding of the nature and evolution of coronal holes and the acceleration and composition of the solar wind. The presentations and discussions occasionally went beyond this topic to include the impact of the reported research on other solar structures and the heliosphere. SOHO (the Solar and Heliospheric Observatory), a project of international cooperation between ESA and NASA, was launched in December 1995 and began its science operations during the first few months of 1996. To many solar and space physicists, it was a great advantage that SOHO began itscomprehensive look at the Sun during the 1996 solar minimum. The qualitatively simple two-phase corona, with polar coronal holes expanding into the high-speed solar wind, and a steady equatorial streamer belt related somehow to the stochastic slow-speed solar wind, allowed various SOHO diagnostics to be initiated with a reasonably well understoodcircumsolar geometry. The analysis of subsequentSOHO measurements made during the rising phase of solar cycle 23 will continue to benefit from what has been learned from the first two years of data.

Seeing Stars is written for astronomers, regardless of the depth of their theoretical knowledge, who are taking their first steps in observational astronomy. Chris Kitchin and Bob Forrest - both professional astronomers - take a conducted tour of the night sky and suggest suitable observing programmes for everyone from beginners to experts. How is this book different? We are all familiar with the beautiful images of planets and galaxies obtained by spacecraft and giant telescopes - but what can you really see with a small telescope? What should you expect from a small refractor or reflector? And what is the effect of observing from a site near a city? The answers are all here, with many photographs that will illustrate exactly what can be seen with different instruments (everything from the naked eye to a 300mm telescope) - and from different locations.

This book by one of the leaders in adaptive optics covers the fundamental theory and then describes in detail how this technology can be applied to large ground-based telescopes to compensate for the effects of atmospheric turbulence. It includes information on basic adaptive optics components and technology, and has chapters devoted to atmospheric turbulence, optical image structure, laser beacons, and overall system design. The chapter on system design is particularly detailed and includes performance estimation and optimization. Combining a clear discussion of physical principles with numerous real-world examples, this book will be a valuable resource for all graduate students and researchers in astronomy and optics.