Highly ionized atoms in the general interstellar gas of the galactic disk were first detected through interstellar absorption line observations of 0 VI with the Copernicus satellite (Rogerson et al. 1973). Survey measurements by Jenkins (1978) of interstellar 0 VI absorption toward 72 stars demonstrated the general presence of 0 VI in the interstellar medium of the galactic disk. This researcIi. and parallel observational studies of the soft X-ra}' background (Williamson et al. 1974; McCammon et al. 1983; Marshall and ClarK 1984) provided direct evidence for the existence of hot low density gas in the mterstellar medium of the galactic disk. The extension of the aDsorption line studies to the distant gas of the galactic halo required the launch of the International Ultraviolet Explorer (IUE) satellite in 1978. The first measures of highly ionized gas m the galactic halo were obtained with the IDE when it was used to record high resolution spectra of bright stars in the Large Magellanic Cloud (Savage and de Boer 1979). Those early spectra revealed the presence of absorption by Si IV and C IV in the galactic nalo and have been followed by a number of surveys with IUE of nighly ionized gas in the galactic disk and halo (Savage and de Boer 1981; Pettini and West 1982; Savage and Massa 1987). The study of UV emission from highly ionized gas in the halo has progressed more slowly because of the intrinsic faintness of the emission.

The Andromeda Galaxy, or M31, is an attractive galaxy for astronomers. It is close to us, it is of about the size of our galaxy, it provides some intriguing observational puzzles because the galaxy is nearly edge-on, and many objects can be studied in detail, because they are still sufficiently bright. With the current developments in instrumentation with which increasingly detailed studies of the Andromeda Galaxy can be made, this book provides a solid foundation for the start of new observations. This book is a mine of information about M31. It can be used as a reference by insiders, and at the same time it provides easy access for newcomers to the field.

The study of planet formation has been revolutionized by recent observational breakthroughs, which have allowed the detection and characterization of extrasolar planets, the imaging of protoplanetary disks, and the discovery of the Solar System's Kuiper Belt. Written for beginning graduate students, this textbook provides a basic understanding of the astrophysical processes that shape the formation of planetary systems. It begins by describing the structure and evolution of protoplanetary disks, moves on to the formation of planetesimals, terrestrial and gas giant planets, and concludes by surveying new theoretical ideas for the early evolution of planetary systems. Covering all phases of planet formation - from protoplanetary disks to the dynamical evolution of planetary systems - this introduction can be understood by readers with backgrounds in planetary science, and observational and theoretical astronomy. It highlights the physical principles underlying planet formation and the areas where more research and new observations are needed.

Peter Gabriel Bergmann started his work on general relativity in 1936 when he moved from Prague to the Institute for Advanced Study in Princeton. Bergmann collaborated with Einstein in an attempt to provide a geometrical unified field theory of gravitation and electromagnetism. Within this program they wrote two articles together: A. Einstein and P. G. Bergmann, Ann. Math. 39, 685 (1938) ; and A. Einstein, V. Bargmann and P. G. Bergmann, Th. von Karman Anniversary Volume 212 (1941). The search for such a theory was intense in the ten years following the birth of general relativity. In recent years, some of the geometrical ideas proposed in these publications have proved essential in contemporary attempts towards the unification of all interactions including gravity, Kaluza-Klein type theories and supergravity theories. In 1942, Bergmann published the book "Introduction to the Theory of Relativity" which included a foreword by Albert Einstein. This book is a reference for the subject, either as a textbook for classroom use or for individual study. A second corrected and enlarged edition of the book was published in 1976. Einstein said in his foreword to the first edition: "Bergmann's book seems to me to satisfy a definite need. . . Much effort has gone into making this book logically and pedagogically satisfactory and Bergmann has spent many hours with me which were devoted to this end.

This proceedings covers topics from chemical abundances in the different components of the Milky Way and in local group galaxies, via observational and theoretical papers on mixing in stars to big bang nucleosynthesis and galaxy formation and evolution. Like all volumes in the series ESO Astrophysics Symposia, this one gives a comprehensive overview of the forefront of research in this subject. It is a valuable reference for both students and researchers.

The emerging study of technology in space has been shaping human interaction with physical, social, and technological worlds. Drawing upon a wide range of information technology disciplines, this field is now grabbing the attention of many, including computer scientists, anthropologists, and psychologists craving for more on this intriguing new field.""Exploration of Space, Technology, and Spatiality: Interdisciplinary Perspectives"" offers stimulating research currently bridging the areas of space, spatiality, and technology. A must-read for researchers and scholars working at the intersection of physical, social, and technological space, this book provides critical research from leading experts in the space technology domain - an essential resource for any academic collection.

Solar Physics publishes up to two TopicalIssues per year that focus on areas of especially vigorousand activeresearch. The present TopicalIssue containspapers of recent results on the solar corona, as well as on the transition region and low solar wind. The majority of these papers, which were all refereed in accordance withthe standards of Solar Physics, werepresentedin August 1999at a workshop heldin Monterey, California. TheSun's magneticfieldis responsibleforthe spectacularly dynamicand intri- cate phenomenonthat we call the corona. The past decade has seen an enormous increase in our understanding of this part of the solar outer atmosphere, both as a result of observations and because of rapid advances in numerical studies.The Yohkoh satellitehasobservedthe Sun nowfor overeightyears, producingspectac- ular sequences of images that conveythe complexity of the corona. The imaging andspectroscopic instrumentsonSOHOhaveaddedinformationonthecoolerpart of the corona. Andsince April of 1998TRACEhas givenus very high resolution imagesof the 1-2 MKcorona, atcadencesthat allowdetailedobservations of field oscillations, loopevolution, mass ejecta, etc. The papers of thisTopicalIssue revolvearoundone keytheme:the entire outer atmosphereof the Sun is intrinsicallydynamic, evolvingso rapidly that even the concept of a single local temperaturefor a single fluid often breaks down. More- over, the corona is an intrinsicallynonlinearand non-localmedium.These aspects are discussedin thisTopicalIssue, includingboth papers that reviewrecentdevel- opments(both basedon observations and on theoretical/numerical modeling), and original research papers based on observations from many different observatories. Weareverygratefulto the manyrefereeswhoweregivenlittletimeto respond, andto the staffofKluwerfor theproductionofthetopicalissuesandtheirreprints. Thepapers acceptedforthisTopicalIssueadduptosuchavolumethattheyhaveto be distributedovertwo TopicalIssues of SolarPhysics (December 1999and April 2000),which are reprintedin two bound volumes, of whichthis is the second.

Even the casual reader cannot fail to notice the somewhat uneven presentation of the contributions contributians to this volume, in particular what concerns the st style. yle. A closer scrutiny will also reveal that whereas the English language is certainly the preferred vehicle for commu- nication in astronomy, it is not the mother tongue of all contributors. However, while editing this volume I have felt that it would be more important to assure a speedy publication than to attempt to achieve a high degree of uniformity, which would anyhow be extremely diffi- cult with more than 100 eontributing contributing authors. When published, this book should stiIl still be a tool for aetive active research, not a museum pieee. piece. I am grateful to the organizers and editors of the individual sections seetions for having produced produeed their parts with within in the allotted time, and with a high degree of professionalism. A special speeial word of thanks goes to my eollaborators collaborators at the European Southern Observatory, Mrs. E. Volk, Volk, Mr. Nr. C. Madsen, and Mr. J. _Leelereqz, _Leclercqz, for technical teehnieal assistanee. assistance.

The XVlllth General Assembly of the International Astronomical Union was held in Patras, Greece, from 17-26 August 1982. It was marked by the tragic death of the President of the IAU, Professor M.K.V. Bappu, on August 19, 1982. This sad event, without precedent in the history of the Union, posed serious problems to the organization of the General Assembly, which could only be overcome by the full collaboration of all members, the organizers, and the Executive Committee. A tribute to the memory of Prof. Bappu was paid during a plenary meeting on 23 August 1982. The full texts of the speeches are published in Chapter I of this . volume. The excellent scientific programme in Patras was organized by the Presidents of the 40 IAU Commissions and coordinated by the IAU General Secretary (1979-1982), Professor P.A. Wayman. The local arrangements were taken care of by Professor C. Goudas and his collaborators from the Patras University. Due to the unexpected withdrawal in 1979 of another invitation to host the 1982 IAU General Assembly, the organizers in Greece had less than two years available for the extensive preparations, and our hearty thanks are due to them for their persistent efforts, which made this General Assembly an outstanding success.

IAU Symposium No. 134 on Active Galactic Nuclei was hosted by the Lick Observatory, as part of the celebration of its centennial, for the Observatory went into operation as part of the University of California on June 1, 1888. Twenty years later, in 1908, Lick Observatory graduate student Edward A. Fath recognized the unusual emission-line character of the spectrum of the nucleus of the spiral "nebula" NGC 1068, an object now well-known as one of the nearest and brightest Seyfert galaxies and active galactic nuclei. Ten years after that, and seventy years before this Symposium, Lick Observatory faculty member Heber D. Curtis published his description of the "curious straight ray" in M 87, "apparently connected with the nucleus by a thin line of matter," which we now recognize as an example of one of the jets which are the subject of so much current AGN research. The symposium was held at Kresge College on the campus of the University of California, Santa Cruz, only a short walk through the redwood groves to the Lick Observatory offices. A total of 232 astronomers and astrophysicists from 24 countries attended and took part in the Symposium. About 200 more had applied to come, but could not be accepted in order to keep the meeting at a reasonable size. Most of the participants lived in the Kresge College apartments immediately adjacent to the Kresge Town Hall in which the oral sessions took place.

This volume, together with its two companion volumes, originated in a study commis sioned by the United States National Academy of Sciences on behalf of the National Aeronautics and Space Administration. A committee composed of Tom Holzer, Dimitri Mihalas, Roger Ulrich and myself was asked to prepare a comprehensive review of current knowledge concerning the physics of the Sun. We were fortunate in being able to persuade many distinguished scientists to gather their forces for the preparation of 21 separate chapters covering not only solar physics but also relevant areas of astrophysics and solar-terrestrial relations. It proved necessary to divide the chapters into three separate volumes that cover three different aspects of solar physics. Volumes II and III are concerned with 'The Solar Atmosphere' and with 'Astrophysics and Solar-Terrestrial Relations'. This volume is devoted to 'The Solar Interior', except that the volume begins with one chapter reviewing the contents of all three volumes. Our study of the solar interior includes a review of nuclear, atomic, radiative, hydrodynamic and hydromagnetic processes, together with reviews of three areas of active current investigation: the dynamo mechanism, internal rotation and magnetic fields, and oscillations. The last topic, in particular, has emerged in recent years as one of the most exciting areas of solar research."

It is not an exaggeration to say that one of the most exciting predictions of Einstein's theory of gravitation is that there may exist "black holes" putative objects whose gravitational fields are so strong that no physical bodies or signals can break free of their pull and escape. The proof that black holes do exist, and an analysis of their properties, would have a significance going far beyond astrophysics. Indeed, what is involved is not just the discovery of yet another even if extremely remarkable, astro physical object, but a test of the correctness of our understanding of the properties of space and time in extremely strong gravitational fields. Theoretical research into the properties of black holes, and into the possible corol laries of the hypothesis that they exist, has been carried out with special vigor since the beginning of the 1970's. In addition to those specific features of black holes that are important for the interpretation of their possible astrophysical manifestations, the theory has revealed a number of unexpected characteristics of physical interactions involving black holes. By the middle of the 1980's a fairly detailed understanding had been achieved of the properties of the black holes, their possible astrophysical manifestations, and the specifics of the various physical processes involved. Even though a completely reliable detection of a black hole had not yet been made at that time, several objects among those scrutinized by astrophysicists were considered as strong candidates to be confirmed as being black holes."

Small and large telescopes are being installed all around the world. Astronomers have thus acquired better access to more modern equipment; not in the least to photometers, which are very important tools for the contemporary observer. This development of higher quality and more sensitive equipment makes it very necessary to improve the accuracy of the measurements. This guide helps the astronomer and astronomy student to improve the quality of their photometric measurements and to extract a maximum of information from their observations. The book is based on the authors' observing experience, spending numerious nights behind various instruments at many different observatories.

Intended for nonspecialists with some knowledge of physics or engineering, The Quantum Beat covers a wide range of salient topics relevant to atomic clocks, treated in a broad intuitive manner with a minimum of mathematical formalism. Detailed descriptions are given of the design principles of the rubidium, cesium, hydrogen maser, and mercury ion standards; the revolutionary changes that the advent of the laser has made possible, such as laser cooling, optical pumping, the formation of optical molasses, and the cesium fountain standard; and the time-based global navigation systems, Loran-C and the Global Positioning System. Also included are topics that bear on the precision and absolute accuracy of standards, such as noise, resonance line shape, the relativistic Doppler effect as well as more general relativistic notions of time relevant to synchronization of remote clocks, and time reversal symmetry. the development of atomic clocks in the first edition, but brings up to date the extraordinary developments in recent years, culminating in clocks based on quantum resonance at optical frequency in individual ions confined in miniature electromagnetic traps. These, together with advances in the generation of wide-band coherent frequency combs spanning the spectrum as far as the optical range, has made possible the direct measurement of phenomena occurring at optical frequencies As a result of these recent advances, in addition to the time-based GPS and LORAN C navigation systems treated in the first edition, other important applications of a fundamental scientific interest have become feasible. These include satellite-borne tests of the theory of general relativity and the equivalence principle on which it is based.

This NATO Advanced Study Institute course provided an updated understanding, from a fundamental and deep point of view, of the progress and current problems in the early universe, cosmic microwave background radiation, large-scale struc ture, dark matter problem, and the interplay between them. Emphasis was placed on the mutual impact of fundamental physics and cosmology, both at the theo retical and experimental or observational levels, within a deep and well defined programme, and a global unifying view, which, in addition, provides of careful inter-disciplinarity. In addition, each course of this series introduced and promoted topics or sub jects which, although not of a purely astrophysical or cosmological nature, were of relevant physical interest for astrophysics and cosmology. Deep understanding, clarification, synthesis, and careful interdisciplinarity within a fundamental physics framework, were the main goals of the course. Lectures ranged from a motivation and pedagogical introduction for students and participants not directly working in the field to the latest developments and most recent results. All lectures were plenary, had the same duration, and were followed by a discus sion. The course brought together experimentalists and theoreticans physicists, astro physicists and astronomers from a wide variety of backgrounds, including young scientists at the post-doctoral level, senior scientists and advanced graduate stu dents as well."

The high accuracy of modern astronomical spatial-temporal reference systems has made them considerably complex. This book offers a comprehensive overview of such systems. It begins with a discussion of 'The Problem of Time', including recent developments in the art of clock making (e.g., optical clocks) and various time scales. The authors address the definitions and realization of spatial coordinates by reference to remote celestial objects such as quasars. After an extensive treatment of classical equinox-based coordinates, new paradigms for setting up a celestial reference system are introduced that no longer refer to the translational and rotational motion of the Earth. The role of relativity in the definition and realization of such systems is clarified. The topics presented in this book are complemented by exercises (with solutions). The authors offer a series of files, written in Maple, a standard computer algebra system, to help readers get a feel for the various models and orders of magnitude. Beyond astrometry, the main fields of application of high-precision astronomical spatial-temporal reference systems and frames are navigation (GPS, interplanetary spacecraft navigation) and global geodynamics, which provide a high-precision Celestial Reference System and its link to any terrestrial spatial-temporal reference system. Mankind's urgent environmental questions can only be answered in the context of appropriate reference systems in which both aspects, space and time, are realized with a sufficiently high level of accuracy. This book addresses all those interested in high-precision reference systems and the various techniques (GPS, Very Long Baseline Interferometry, Satellite Laser Ranging, Lunar Laser Ranging) necessary for their realization, including the production and dissemination of time signals.

The imaging process in stellar interferometers is explained starting from first principles on wave propagation and diffraction. Wave propagation through turbulence is described in detail using Kolmogorov statistics. The impact of turbulence on the imaging process is discussed both for single telescopes and for interferometers. Correction methods (adaptive optics and fringe tracking) are presented including wavefront sensing/fringe sensing methods and closed loop operation. Instrumental techniques like beam combination and visibility measurements (modulus and phase) as well as Nulling and heterodyne interferometry are described. The book closes with examples of observing programmes linking the theory with individual astrophysical programmes.

This book contains the expanded lecture notes of the 32nd Saas-Fee Advanced Course. The three contributions present the central themes in modern research on the cold universe, ranging from cold objects at large distances to the physics of dust in cold clouds.

This textbook provides details of the derivation of Lagrange's planetary equations and of the closely related Gauss's variational equations, thereby covering a sorely needed topic in existing literature. Analytical solutions can help verify the results of numerical work, giving one confidence that his or her analysis is correct. The authors-all experienced experts in astrodynamics and space missions-take on the massive derivation problem step by step in order to help readers identify and understand possible analytical solutions in their own endeavors. The stages are elementary yet rigorous; suggested student research project topics are provided. After deriving the variational equations, the authors apply them to many interesting problems, including the Earth-Moon system, the effect of an oblate planet, the perturbation of Mercury's orbit due to General Relativity, and the perturbation due to atmospheric drag. Along the way, they introduce several useful techniques such as averaging, Poincare's method of small parameters, and variation of parameters. In the end, this textbook will help students, practicing engineers, and professionals across the fields of astrodynamics, astronomy, dynamics, physics, planetary science, spacecraft missions, and others. "An extensive, detailed, yet still easy-to-follow presentation of the field of orbital perturbations." - Prof. Hanspeter Schaub, Smead Aerospace Engineering Sciences Department, University of Colorado, Boulder "This book, based on decades of teaching experience, is an invaluable resource for aerospace engineering students and practitioners alike who need an in-depth understanding of the equations they use." - Dr. Jean Albert Kechichian, The Aerospace Corporation, Retired "Today we look at perturbations through the lens of the modern computer. But knowing the why and the how is equally important. In this well organized and thorough compendium of equations and derivations, the authors bring some of the relevant gems from the past back into the contemporary literature." - Dr. David A Vallado, Senior Research Astrodynamicist, COMSPOC "The book presentation is with the thoroughness that one always sees with these authors. Their theoretical development is followed with a set of Earth orbiting and Solar System examples demonstrating the application of Lagrange's planetary equations for systems with both conservative and nonconservative forces, some of which are not seen in orbital mechanics books." - Prof. Kyle T. Alfriend, University Distinguished Professor, Texas A&M University

The mono graph contains 8 chapters, and their contents cover all principal aspects of the problem: 1. Introduction and brief his tory ofthe radiation problem and background information ofradiation hazard in the near-Earth and interplanetary space. 2. General description of radiation conditions and main sources of charged partic1es in the Earth's environment and interplanetary space, effects of space environment on spacecraft. 3. Basic information about physical conditions in space and main sources of charged particles in the Earth's environment and interplanetary space, in the context of "Space W eather" monitoring and prediction. 4. Trapped radiation belts of the Earth (ERB): theory of their origin, spatial and temporal dynamics, and experimental and statistical models. 5. Galactic cosmic rays (GCR): variations of energetic, temporal and spatial characteristics, long-term modulation, and anomalous cosmic ray (ACR) component, modeling oftheir dynamics. 6. Production of energetic particles (SEPs) at/ne ar the Sun: available databases, acceleration, propagation, and prediction of individual SEP event, statistical models of solar cosmic rays (SCR). 7. Existing empirical techniques of estimating, prediction and modeling of radiation hazard, methodical approaches and constraints, some questions of changes in the Earth's radiation environment due to changes of the solar activity level. 8. Unresolved problems of radiation hazard prediction and spacecraft protection, radiation experiments on board the spacecraft, estimating of radiation conditions during interplanetary missions. Space does not allow us to explain every time the solar-terrestrial and radiation physics nomencIature used in current English-language literature.

Since the publication of The New Science of Astrobiology in the year 2001 the first edition of the present book two significant events have taken place raising the subject from the beginning of the present century to its present maturity. Firstly, in 2001 the Galileo Mission still had two years to complete its task, which turned out to be an outstanding survey of the Jovian system, especially of its intriguing satellite Europa. Secondly, the Cassini Huygens Mission was still on its way to Saturn. Its present success has surpassed all expectations of ESA and NASA. Astrobiologists still did not know that Titan was the fifth body in the Solar System that possibly contained a water ocean (including the Earth and the three Galilean satellites other than Io). For these reasons the book includes overviews of the evolutionary and molecular biology that are necessary. There is a discussion of other sectors of culture that are the natural frontiers of astrobiology, especially the humanities."

Astrophysics is facing challenging aims such as deep cosmology at redshift higher than 10 to constrain cosmology models, or the detection of exoplanets, and possibly terrestrial exoplanets, and several others. It requires unprecedented ambitious R&D programs, which have definitely to rely on a tight cooperation between astrophysics and optics communities. The book addresses most of the most critical interdisciplinary domains where they interact, or where they will do. A first need is to collect more light, i.e. telescopes still larger than the current 8-10 meter class ones. Decametric, and even hectometric, optical (from UV to IR wavelengths) telescopes are being studied. Whereas up to now the light collecting surface of new telescopes was approximately 4 times that of the previous generation, now this factor is growing to 10 to 100. This quantum leap urges to implement new methods or technologies developed in the optics community, both in academic labs and in the industry. Given the astrophysical goals and technological constraints, new generation adaptive optics with a huge number of actuators and laser guide stars devices have to be developed, from theoretical bases to experimental works. Two other newcomers in observational astrophysics are interferometric arrays of optical telescopes and gravitational wave detectors. Up-to-date reviews of detectors and of spectrographs are given, as well as forefront R&D in the field of optical coatings and of guided optics. Possible new ways to handle photons are also addressed, based on quantum physics. More and more signal processing algorithms are a part and parcel of any modern instrumentation. Thus finally the book gives two reviews about wavefront processing and about image restoration and deconvolution algorithms for ill conditioned cases.

The book summarizes international progress over the last few decades in upper atmosphere airglow research. Measurement methods, theoretical concepts and empirical models of a wide spectrum of upper atmospheric emissions and their variability are considered. The book contains a detailed bibliography of studies related to the upper atmosphere airglow. Readers will also benefit from a lot of useful information on emission characteristics and its formation processes found the book.

The workshop on The Cosmology of Extra Dimensions and Varying Fundamental Constants, which was part of JENAM 2002, was held at the Physics Department of the University of Porto (FCUP) from the 3rd to the 5th of September 2002. It was regularly attended by about 110 participants, of which 65 were officially registered in the VFC workshop, while the others came from the rest of the JENAM workshops. There were also a few science correspondents from the national and international press. During the 3 days of the scientific programme, 8 Invited Reviews and 30 Oral Communications were presented. The speakers came from 11 different European countries, and also from Argentina, Australia, Canada, Japan and the U.S.A. There were also speakers from six Portuguese research institutions, and nine of the speak ers were Ph.D. students. The contributions are presented in these proceedings in chronological order. The workshop brought together string theorists, particle physicists, theoretical and observational cosmologists, relativists and observational astrophysicists. It was generally agreed that this inter-disciplinarity was the greatest strength of the work shop, since it provided people coming into this very recent topic from the various different backgrounds with an opportunity to understand each other's language and thereby gain a more solid understanding of the overall picture."