This text comprises selected lectures presented in the 9th course of the International School of Cosmic-Ray Astrophysics held at the Ettore Majorana Centre in Erice, Sicily, May 7-18, 1994. Devoted to problems and prospects in high-energy astrophysics and cosmology, the major areas explored are: gamma- ray, X-ray, and neutrino astronomies; cosmic rays; pulsars and supernova remnants; and cosmology, as well as cosmogony. Among the principal developments in gamma-ray astrophysics are those generated by the Compton Gamma Ray Observatory. Cosmic neutrinos at MeV energies, i.e. those from the Sun and from Supernova 1987a are discussed, as well as neutrino masses in astrophysics. The source composition of cosmic rays and extensive air shower experiments receive special attention. The early universe according to COBE data, and as viewed by theorists of cosmology, is reviewed.

This Symposium on fundamental stellar properties was held to honour Emeritus Professor Robert Hanbury Brown on the occasion of his 80th birthday. The speakers described current advances in interferometry, astrometry, spectroscopy and in theoretical models of stellar atmospheres and interiors. The emphasis was on the critical assessment of the quality, accuracy, and prospects for improvement of the observational data and theoretical models, on the outstanding problems in stellar astrophysics, and on the feasibility of achieving the observational and theoretical advances required for their solution. These proceedings should be of interest to researchers and graduate students in all fields of astrophysics.

This book highlights selected topics of standard and modern theory of accretion onto black holes and magnetized neutron stars. The structure of stationary standard discs and non-stationary viscous processes in accretion discs are discussed to the highest degree of accuracy analytic theory can provide, including relativistic effects in flat and warped discs around black holes. A special chapter is dedicated to a new theory of subsonic settling accretion onto a rotating magnetized neutron star. The book also describes supercritical accretion in quasars and its manifestation in lensing events. Several chapters cover the underlying physics of viscosity in astrophysical discs with some important aspects of turbulent viscosity generation. The book is aimed at specialists as well as graduate students interested in the field of theoretical astrophysics.

Following the 'Big Bang', it took the universe billions of years to evolve into the unique system of stars and planets that we know of today. Scientists have studied the planets of our solar system for centuries, and are beginning to understand the billions of stars and other bodies that make up the Universe. Stars and Planets is an ideal reference book for anyone interested in astronomy, featuring 300 of the most well known stars, planets, moons, constellations and other cosmological phenomena, such as black holes and quasars. Each entry includes an image - either a photograph or an artist's impression or diagram - and a key information table including specifications such as the mass, radius, surface temperature, distance from sun, gravity and major elements of each object. Presented in a handy, pocket-size format, full of facts and engaging text, Stars and Planets is a valuable reference source as well as a fascinating read, revealing the spectacular world of the Cosmos.

Evolution of Stars and Stellar Populations is a comprehensive presentation of the theory of stellar evolution and its application to the study of stellar populations in galaxies. Taking a unique approach to the subject, this self-contained text introduces first the theory of stellar evolution in a clear and accessible manner, with particular emphasis placed on explaining the evolution with time of observable stellar properties, such as luminosities and surface chemical abundances. This is followed by a detailed presentation and discussion of a broad range of related techniques, that are widely applied by researchers in the field to investigate the formation and evolution of galaxies.
This book will be invaluable for undergraduates and graduate students in astronomy and astrophysics, and will also be of interest to researchers working in the field of Galactic, extragalactic astronomy and cosmology.
* comprehensive presentation of stellar evolution theory
* introduces the concept of stellar population and describes "stellar population synthesis" methods to study ages and star formation histories of star clusters and galaxies.
* presents stellar evolution as a tool for investigating the evolution of galaxies and of the universe in general.

4. Census of the Catalogue The catalogue contains information on 277 objects. 137 (50%) of them are stars whose outburst spectra or unambiguous mInImUm characteristics classify them as novae beyond doubt. 123 of them could be identified at minimum. 78 (28 %) are stars with amplitudes and light curve forms which makes nova classifi cation likely. 60 of them could be identified at minimum. Thus, 78 % ofthe objects in this catalogue are confirmed and suspected classical novae. 16 (6%) have properties compatible with both novae and related objects. 15 are identified at minimum. Furthermore, the catalogue and atlas contains data on 12 (4 %) dwarf novae of long cycle length or suspected dwarf novae for which only one outburst has been observed. Examples are WZ Sge and CI Gern. 6 (2%) recurrent novae or suspected recurrent novae are listed. Examples are T CrB and AS Psc. 6 (2%) X-ray novae are listed. Examples are V616 Mon and KY TrA. 6 (2%) symbiotic stars and symbiotic novae are listed. Examples are RT Ser and V352 Aql. 11 (4 %) Mira stars or suspected Mira stars, which at some time were believed to be novae, are listed. Examples are V607 Aql and V927 Sgr."

This is a review of the basic elements directly connected to the evolution of galaxies. Owing to advances in observational astronomy and astrophysics, data has become available about remote galaxies, which are consequently in the first stages of their evolution. It is therefore essential to link these data to the observation of very old populations in our own Galaxy, which are the remnants of the populations which existed in the first stages of galactic evolution. In this meeting, the relationship between these two different points of view is emphasized in the texts presented by well-known specialists as well as by young researchers active in the field. The difficulties of the problem and the remaining uncertainties are discussed.

Research of the interstellar medium (ISM) has been advancing rapidly during the last 10 years, mainly due to immensely improved observational facilities and techniques in all wavelength ranges. We are now able to investigate the ISM in external galaxies and even the intergalactic and intracluster medium in great detail. Increased spatial and spectral resolution have provided us with a great deal of information on the interstellar gas in its various phases, the magnetic field and the cosmic rays, and of course, also the stellar component, which is the driving agent of the interstellar matter cycle.
Since only fairly recently, a sufficient amount of computing power has become available to tackle these problems with some prospect of obtaining a self-consistent picture of the ISM, a major goal of this workshop was to bring together observers and theoreticians sufficiently close, so that intense discussions about the necessities and desiderata of modelling the ISM could be stimulated. Observers have shown in great detail on this conference of what is seen on all scales of the ISM, near and far, and what boundary conditions would be appropriate for realistic models, and theoreticians pointed out what assumptions and simplifications their codes need, and how future observations could test their models. As a first step towards this goal, some self-consistent numerical simulations with a minimum number of relevant physical processes were also presented on this meeting. There was wide agreement, that this approach - to keep observers and theoreticians in close contact and also in sometimes quite controversial discussions - will bear fruitful results in the near future.

In this Symposium, researchers specializing in pulsation, rotation, magnetic fields and stellar winds are brought together for the first time in order to broaden our understanding of O and B stars. Thanks to advances in digital spectroscopy, new types of pulsating B stars have been discovered. The pulsations can be understood in terms of the recent revision of metal opacities, but the effects of rapid rotation and magnetic fields need further study. Observations in the UV and X-ray regions demonstrate that many B and Be stars show other activity, besides pulsation which is not yet understood. The reason for the enhanced mass loss in B stars is a question which dominates the Symposium and which remains unanswered, although it is surely to be found in activity at or near the photosphere coupled with rotation. It is shown that the geometry of the circumstellar envelopes around Be stars is indeed a flattened disk as they can now be optically resolved. The variability of radiatively-driven winds from O and B stars are likely related to the rotation of the star. This underlines the central theme of the book: that the various phenomena seen in these stars cannot be studied in isolation.

The mystery of gravity has captivated us for centuries. But what is gravity and how does it work? This engaging book delves into the bizarre and often counter-intuitive world of gravitational physics. Join distinguished astrophysicist Professor Luciano Rezzolla on this virtual journey into Einstein's world of gravity, with each milestone presenting ever more fascinating aspects of gravitation. Through gentle exposure to concepts such as spacetime curvature and general relativity, you will discover some of the most curious consequences of gravitational physics, such as black holes, neutron stars and gravitational waves. The author presents and explains one of the most impressive scientific achievements of recent times: the first image of a supermassive black hole. Written by one of the key scientists involved in producing these results, you'll get a behind-the-scenes view of how the image was captured and discover what happens to matter and light near a black hole.

In July 1992, over 300 astronomers attended the Third Tetons Summer School on the subject of "The Environment and Evolution of Galaxies". This book presents 28 papers based on invited review talks and a panel discussion on "The Nature of High Redshift Objects". The major themes include: the interstellar and intergalactic medium, galaxy formation and evolution, cooling flows, quasars and radiation backgrounds, and interactions between galaxies/AGNs and their environment. Recent advances with the ROSAT, COBE and Hubble Space Telescope are discussed, together with current theoretical developments. The tutorial nature of the papers should make this book a useful supplement for professional astonomers, graduate students, and senior undergraduates. As with previous Tetons conferences, this book provides both the current state of observational and theoretical research and material complementary to courses in extragalactic and interstellar astrophysics.

The papers in this study cover a range of scenarios, from disk and envelope around young stellar objects and protostars through to more aged stars and highly-evolved objects which exhibit considerable mass loss features. Significant advances and developments in observing facilities, instrumentation, computing power and techniques are described, together with a variety of theories, suggestions, observations and models. The formation, composition, effects and evolution of the material surrounding a stellar environment are also included.

The motivation for the workshop on which this book is based was the discovery in recent years of a large number of binary and millisecond radio pulsars, in the galactic disk as well as in globular star clusters, the oldest stellar systems in our galaxy. These discoveries have revolutionized our thinking on many aspects concerning the interior structure and evolution of neutron stars, and have revived the interest in the study of neutron star physics in general. In this book some three dozen of the world's experts in the field of radio pulsars, X-ray binaries, stellar evolution, neutron star interiors and stellar dynamics review the latest observational discoveries as well as the current theoretical thinking on the formation and physics of binary X-ray sources and of the binary and milli-second pulsars. These include discoveries such as that of the elevent millisecond pulsars in the globular cluster 47 Tucanae, the relativistic effects in the new double neturon star system PSR 1534+12 and spectacular results from Germany's ROSAT X-Ray Observatory.

Foreword; J. Davies, D. Burstein. Introductory Remarks; M. Disney. Interstellar grain evolution and temperatures in spiral galaxies; J. Mayo Greenberg, A. Li. Radiative transfer models; G. Bruzual A. Radiative transfer in dusty galaxies; A.N. Witt. Opacity Diagnostics in spiral galaxies; N.D. Kylafis. Modeling dusty galaxies; G. Magris C., G. Bruzual A. Inclination-dependence of spiral galaxy physical properties: history and tests; D. Burstein, et al. Why a distance selection effect invalidates the Burstein, Haynes and Faber opacity test; J.I. Davies, et al. Statistical tests for opacity; E.A. Valentijn. Statistical measures of internal absorption in spiral galaxies; B. Cunow. The distribution of galactic inclinations; H. Jones, et al. Optical thickness of Sb-Scd galaxies from the Tully--Fisher relation; L. Gouguenhei, et al. Extinction in Sc galaxies at I band and in the 21cm line; R. Giovanelli. Extinction in the galaxy and in galactic discs; G. de Vaucouleurs. Properties of dust in backlit galaxies; W. Keel, R.E. White. The optical depth through NGC 3314A; P. James, P. Puxley. Dust extinction in highly inclined spirals; J. Knapen, et al. An optical search for dusty disks; M. Naslund, S. Joersater. Photometric asymmetry and dust opacity of spiral galaxies; Y.I. Byun. The scale-length test for dust in face-on spirals; J.E. Beckman, et al. Color gradients in spiral galaxies; S. Courteau, J. Holtzman. Constraints on the opacity of spiral disks from near-infrared observations; H.W. Rix. Arcsecond resolution of cold dust in spiral galaxies using optical and NIR imaging -- dust masses increase by nine hundred percent; D.L. Block, et al. Unveiling stars and dust in spiral galaxies;R.F. Pelletier, et al. Azimuthal distribution of dust in NGC 2997; P. Grosbol, et al. Internal extinction in spiral galaxies at optical and near infrared wavelengths; A. Boselli, G. Gavazzi. The opacity of spiral galaxy disks; N. Devereux. The far infrared/stellar energy balance; R. Evans. Opacity from luminosity functions; M. Trewhella, et al. Estimating disk opacities using infrared images; W. van Driel. DIRBE observations of galactic extinction; R.G. Arendt, et al. Kinematics of edge-on galaxies and the opacity of spiral disks; A. Bosma. Spectroscopic studies of the disk and halo of M82; C.D. McKeith, et al. Disk origin and evolution; J. Silk. The luminosity and opacity of galaxies; B. Wang. Dust obscuration in starburst galaxies; D. Calzetti. Polarimetry of dusty edge-on galaxies; R.D. Wolstencroft, S.M. Scarrott. HII regions and extinction in the spiral galaxy M83; S. Ryder, et al. A search for dust in galactic halos; D. Zaritsky. Concluding thoughts and reflections: dust in galaxies; H.A. Thronson Jr.

Planetary nebulae are a keystone for the understanding of the evolution of stars, for deep insights into the physical processes prevailing in highly excited dilute nebulae, and for the chemical evolution in galaxies. These objects, displaying an intriguing morphology, have a "short" lifetime of a few tens of thousands of years, and have become one of the best studied classes of celestial sources. However, despite large and successful efforts from both the observational and theoretical side, planetary nebulae still keep some of their secrets (like the widely unknown distances) and will undoubtedly also be objects of thorough investigations in the years to come.

The observational evidence for the existence of black holes has grown significantly over recent decades. Stellar-mass black holes are detected as X-ray sources in binary systems, while supermassive black holes, with masses more than a million times the mass of the Sun, lurk in the nuclei of galaxies. These proceedings provide a useful and up-to-date overview of the observations of black holes in binaries, in the center of the Milky Way, and in the nuclei of galaxies, presented by leading expert astronomers. Special attention is given to the formation (including the recent evidence from gamma-ray bursts), physical properties, and demographics of black holes.

The recent meeting of the world's white dwarf specialists was held in Leicester, in July 1992, reporting on the wealth of astronomical data that has been made available from a new generation of space-based observatories and recent theoretical advances which are essential for interpretation of the results. Astronomers now have access to previously unavailable spectral ranges and dramatically improved sensitivity in those wavebands already explored. Results from the ROSAT all-sky survey, Hubble Space Telescope, Hopkins Ultraviolet Telescope and the Colorado Rocket-borne Spectrometer shed new light on the composition of white dwarfs and their evolution. Considerable progress has been made in understanding the internal structure of white dwarfs with asteroseismological techniques which are outlined in several papers. New observational results, which utilize this theoretical work are also presented. This text is suitable for graduate students and postdoctoral researchers interested in isolated white dwarfs or binary systems containing a white dwarf component.

These proceedings of a workshop held at Isle-aux-Coudres, Quebec, Canada in August 1993, provide an assessment of a fundamental subject in modern stellar astrophysics. Hot, luminous stars play a crucial role in the rapid recycling of matter in dense regions of the Universe. The most luminous objects generate the strongest outflows of material, which in turn have a profound impact on both the interstellar medium and the underlying stars themselves. However, recent observational and theoretical advances have shown that these outflows are highly unstable and inhomogeneous. These characteristics constitute a fundamental property of the outflows that can no longer be disregarded. This text provides an assessment of this important phenomenon from both an observational and a theoretical perspective. It includes up-to- date discussions of the observational diagnostics of time-dependent stellar-wind structure, the theoretical understanding of the origin of such structures, and its consequences for the process of mass loss via stellar winds.

Editing the proceedings of a scientific meeting is not an easy task. Sometimes people who give an excellent talk do not send the manuscript by the deadline. However, this time, thanks to the punctuality of all the participants, we have this excellent volume for the workshop on mass losing pulsating stars and their circumstellar matter prepared in time. Almost all of the oral presentations including the summary are collected in this volume. We regret that we cannot put in this volume a few posters that we failed to receive before the editorial work. The workshop was planned as a small meeting with less than fifty attendants because the city of Sendai was far from the most of the active institutions. However, the number of submitted papers exceeded the SOC's expectation; many interesting contributions had to be scheduled in the poster session. Still, the oral sessions were so tight that many participants might have felt frustrated for the shortage of discussions. The organizers of the workshop have to apologize to the attendants for the inconvenience caused from such a happy underestimate about the size of the workshop."

Black holes are undoubtedly one of the most fascinating discoveries of modern astronomy, and their description one of the most daring intellectual feats of modern times. They have already become legendary, forming the basis of many myths, fantasies and science fiction movies. Are they really the monsters which devour light and stars; bottomless celestial pits into which all matter is sucked and crushed? Are they an observable reality, or are they just hypothetical objects from the theory of relativity? In answering such questions the author takes us on a fabulous journey through space and time. Dr Jean-Pierre Luminet is an astronomer at Meudon Observatory in France, a specialist on the subject of black holes, and has also acquired a reputation for being a gifted writer and communicator. In this book he makes the subject of black holes accessible to any interested reader, who will need no mathematical background.

Symposium No. 88 of the International Astronomical Union was devoted to a comprehensive review of all types of close.binary stars. The nine sessions were organized according to the type of the objects to be discussed. We have preserved this system, but assembled twelve papers of a more general character (reviews and surveys) into a special chapter placed at the beginning of this book. We would like to remind the reader that the Symposium was preceded by the IAU Colloquium No. 53 on White Dwarfs and Variable Degenerate Stars , and that the sessions on Cataclysmic Variables and related topics at the two meetings supplemented each other. The discussion in Toronto was carefully recorded by Mr. Robert Gauthier. We also wish to thank Mr. Robert O'Daniel, Ms. Joan Kaufmann, and Ms. Linda Reimers for assisting us with the editorial work. M. J. Plavec D. M. Popper R. K. Ulrich ACKNOWLEDGEMENTS The International Astronomical Union and the University of Toronto contributed substantial funds enabling a number of participants to receive travel grants. The Symposium was sponsored by the following Commissions of the International Astronomical Union: 29 (Stellar Spectra), 30 (Radial Velocities), 35 (Stellar Structure), 42 (Close Binary Stars), and 44 (Astronomy from Space). Our special thanks go to the members of the Scientific Organizing Committee. The Symposium was attended by 170 participants from 26 countries.

Streamlining the extensive information from the original, highly acclaimed monograph, this new An Introduction to the Physics of Interstellar Dust provides a concise reference and overview of interstellar dust and the interstellar medium. Drawn from a graduate course taught by the author, a highly regarded figure in the field, this all-in-one book emphasizes astronomical formulae and astronomical problems to give a solid foundation for the further study of interstellar medium. Covering all phenomena associated with cosmic dust, this inclusive text eliminates the need to consult special physical literature by providing a comprehensive introduction in one source. The book addresses the absorption and scattering of dust, its creation in old stars, as well as emission, cohesion, and electrical charge. With strong attention to detail, the author facilitates a complete understanding from which to build a more versatile application and manipulation of the information. Providing insightful explanations for the utilization of many formulae, the author instructs in the effective investigation of astronomical objects for determining basic parameters. The book offers numerous figures displaying basic properties of dust such as optical constants, specific heat, and absorption and scattering coefficients making it accessible for the reader to apply these numbers to the problem at hand. There is an extensive section and comprehensive introduction to radiative transfer in a dusty medium with many practical pieces of advice and ample illustrations to guide astronomers wishing to implement radiative transfer code themselves. An unparalleled amount of astronomical information in an accessible andpalatable resource, An Introduction to the Physics of Interstellar Dust provides the most complete foundational reference available on the subject.

This book contains the proceedings of the first large IAU Symposium dedicated to the bulges of spiral galaxies. Detailed attention is paid to the bulge of the Milky Way, one of the major building blocks of this system. Topics include the definition of the bulge in our Galaxy and its relation to the so-called spheroid. Discussions are presented regarding the stars contained in this bulge, their astrophysical properties, their motions and the metallicity variations which appear to be present. The possible existence of a bar in the bulge and its origin and future are also examined. The same topics are discussed in less detail for the bulges of other galaxies.

Interstellar dust grains catalyse chemical reactions, absorb, scatter, polarise and re-radiate starlight and constitute the building blocks for the formation of planets. Understanding this interstellar component is therefore of primary importance in many areas of astronomy & astrophysics. For example, observers need to understand how dust effects light passing through molecular clouds. Astrophysicists wish to comprehend how dust enables the collapse of clouds or how it determines the spectral behaviour of protostars, star forming regions or whole galaxies. This book gives a thorough theoretical description of the fundamental physics of interstellar dust: its composition, morphology, size distribution, dynamics, optical and thermal properties, alignment, polarisation, scattering, radiation and spectral features.
This encyclopedic book provides the basic physics towards understanding the solid matter in interstellar space. It includes all the necessary physics, including solid state physics, radiative transport, optical properties, thermodynamics, statistical mechanics and quantum mechanics. It then uses all of this basic physics in the specific case of dust grains in the interstellar medium.
Interstellar dust clouds catalyze simple chemical reactions, absorbs, scatters, polarizes and re-radiates starlight and forms the building blocks for planet and stellar formation. Understanding this interstellar medium is then of primary importance in many areas of astronomy & astrophysics. For example observers need to understand how it effects light passing through dust and molecular clouds, astrophysicists need to comprehend the formation and structure of dust clouds and how it collapses to form stars and planets.
Written in an accessible and descriptive manner, this will be essential supplementary reading for advanced undergraduate and graduate students taking courses on the interstellar medium and active researchers in need of a single source of well illustrated and detailed information.

Olbers' paradox states that given the Universe is unbounded, governed by the standard laws of physics, and populated by light sources, the night sky should be ablaze with light. Obviously this is not so. However, the paradox does not lie in nature but in our understanding of physics. A Universe with a finite age, such as follows from big-bang theory, necessarily has galaxies of finite age. This means we can only see some of the galaxies in the Universe, which is the main reason why the night sky is dark. Just how dark can be calculated using the astrophysics of galaxies and stars and the dynamics of relativistic cosmology.
We know from the dynamics of individual galaxies and clusters of galaxies that the majority of matter that exerts gravitational forces is not detectable by conventional telescopes. This dark matter could have many forms, and candidates include various types of elementary particles as well as vacuum fluctuations, black holes, and others. Most of these candidates are unstable to decay and produce photons. So dark matter does not only affect the dynamics of the Universe, but the intensity of intergalactic radiation as well. Conversely, we can use observations of background radiation to constrain the nature and density of dark matter.
By comparing observational data with cosmological theory based on general relativity and particle physics, Dark Sky, Dark Matter reviews our present understanding of the universe and the astrophysics of the night sky and dark matter.