Set against the background of beautiful Mirabello Bay, astronomers from fourteen countries met at Elounda, Crete in the period 7-18June, 1999 to debate some of the most compelling issues of present day astrophysics. Neutron stars and black holes have been at the forefront of astrophysics for over thirty years. As recently as ten years ago it was still being debated whether galactic stellar-mass black holes existed or not.It is now generally accepted that many (possibly a thousand) stellar-mass black holes - most of them still undetected - lie in low mass X-ray binary (LMXB) systems; a few of them are detected every year as X-ray or gamma-ray transients. These objects are more massive than 3 M, the maximum possible mass 0 for a neutron star, and show none of the tell-tale signs of neutron stars, such as X-ray bursts and X-ray pulsations. It is quite remarkable that all LMXBs display a similar temporal and spectral behaviour, 'independently of whether the accreting compact object is a neutron star or a black hole. A broad debate on these similarities and differences naturally constituted one of the main focal points during the Elounda meeting. Evidence on these aspects has been forthcoming from the Compton Gamma-ray Observatory (CGRO), the ROSAT and ASCA satellites, the Rossi X-Ray Timing Explorer (RXTE), and from the Beppo SAX Observatory."

It has been more than five decades ago that Henk van de Hulst predicted the observability of the 21-cm line of neutral hydrogen (HI ). Since then use of the 21-cm line has greatly improved our knowledge in many fields and has been used for galactic structure studies, studies of the interstellar medium (ISM) in the Milky Way and other galaxies, studies of the mass distribution of the Milky Way and other galaxies, studies of spiral struc ture, studies of high velocity gas in the Milky Way and other galaxies, for measuring distances using the Tully-Fisher relation etc. Regarding studies of the ISM, there have been a number of instrumen tal developments over the past decade: large CCD's became available on optical telescopes, radio synthesis offered sensitive imaging capabilities, not only in the classical 21-cm HI line but also in the mm-transitions of CO and other molecules, and X-ray imaging capabilities became available to measure the hot component of the ISM. These developments meant that Milky Way was no longer the exclusive playground for ISM studies and that by reaching out to other galaxies astronomy had gained the advantage of having an "outside" view, though at the expense of giving up some linear resolution. Studies of the ISM in other galaxies are intimately connected to studies of the ISM in the Milky Way."

A wide range of topics are covered, ranging from supernovae to active galactic nuclei, cosmic gamma rays to neutrinos and dark matter. The basic emphasis is on physics / astrophysics and experimental / observational techniques, scientific implications of current results, and prospects for future advances. The fields surveyed are in rapid development and the exploration of our high energy universe is proceeding rapidly, with exciting new discoveries. What unifies much of the new data is the idea of particle acceleration to enormous energies and the subsequent interactions of the particles with the local medium. It this focus that makes the book both timely and an important contribution to the field.

Observing variable stars is one of the major contributions amateur astronomers make to science. There are 36,000 variable stars listed in the General Catalogue of Variable Stars, so it is clearly impossible for the limited number of professional observatories to target even the majority of them. That's where amateur astronomers come in - thousands of them turning their telescopes to the sky every night. Variable star observing is the most popular of "real science" activities for amateurs, and Gerry Good's book provides everything needed. The first part of the book provides a highly detailed account of the various classes of variable star, with examples, illustrations and physical descriptions. The second section covers practical aspects of observing, everything from preparation and planning, through observing techniques, to data management and reduction.

The gravitational million-body problem is a model for understanding the dynamics of rich star clusters. This text describes the theory astronomers need for studying globular star clusters. After introducing the million-body problem from various view-points, the book systematically develops the tools needed for studying the million-body problems in nature, and introduces the most important theoretical models. Written for graduate students and researchers in astrophysics and astronomy, this text also has important applications in the fields of theoretical physics, computational science and mathematics.

The atmospheres of many stars have chemical compositions that are significantly different from that of the interstellar medium from which they are formed. This symposium considered all kinds of late-type stars showing altered compositions, the carbon stars being simply the best-known of these. All stages of stellar evolution from the main sequence to the ejection of a planetary nebula were considered, with emphasis on the changes that occur on the asymptotic giant branch. The spectroscopic properties of the photospheres and circumstellar envelopes of chemically-peculiar red giant stars, their origins via single-star evolution or mass transfer in binary systems, and the methods currently used to study them in 2000 were all discussed in detail. This volume includes the full texts of papers given orally at the symposium and abstracts of the posters.

Pulsating and eccentric binary stars play a fundamentally important role in deciphering the mass distribution within stars. The present volume reviews the fundamental concepts of both radial and nonradial oscillations in the stars, including the Sun. Helio- and astroseismological results are reviewed, from the basics to the most recent developments. A new theory is presented, which seems to explain the mechanism of the light and radial velocity variations of recently discovered Ap stars. This textbook covers almost all kinds of variable stars of widely different characteristics. It will serve as a reference text for a very long time to come, not only for specialists but also for undergraduate students of physics and astronomy.

Binary systems of stars are as common as single stars. This original text provides a pedagogical and comprehensive introduction to binary stars. The author combines theory and observations at all wavelengths to develop a unified understanding of binaries of all categories. Chapters review methods for calculating orbits, the Roche model, ideas about mass exchange and loss, methods for analyzing light curves, the masses and dimensions of different binary systems, and imaging the surfaces of stars and accretion structures. This volume offers advanced undergraduate and graduate students a thorough introduction to binary stars that will aid their learning of stellar astrophysics, stellar structure and evolution, and observational astrophysics.

A few years after the publication of The Physics of Star Formation and Early Stellar Evolution, we received a request from the publisher for an up dated second edition of this popular reference book. As originally intended, the volume had proved to be a useful "text" book for graduate astronomy courses and seminars which dealt with topics related to stellar origins. The book was based on a series of lectures delivered by a distinguished group of leading researchers at a NATO Advanced Study Institute (ASI) held in May 1990 on the island of Crete, Greece. The primary goal of the ASI was in fact to produce a book which "would simultaneously provide a broad and systematic overview of, as well as a rigorous introduction to, the fun damental physics and astronomy at the heart of modern research in star formation and early stellar evolution. " However, by 1995 concern had arisen among those who used the text as a reference for graduate seminars and courses that the book would need to be updated to stay abreast of the discoveries and progress in this rapidly evolving field. After some discussion we concluded that a new edition of the book was warranted and that the goal of producing a new edition would be best accomplished by organizing a second ASI in Crete to review the progress in star formation research."

The 186th IAU Symposium came at an exciting and perhaps even historic time for extragalactic astronomy. New spacecraft observations plumbed the depths of the Universe out to redshifts of five, while revealing astounding details of nearby galaxies and AGN at intermediate redshifts. Theoretical ideas on structure formation, together with results from detailed numerical modeling, created a comprehensive framework for modeling the formation of galaxies and the transformation of galaxies by interactions and mergers. All these strands came together at the Symposium, as participants glimpsed a developing synthesis highlighting galactic encounters and their role in the history of the Universe. This volume offers professional astronomers, including PhD students, an overview of the rapidly advancing subject of galaxy interactions at low and high redshifts.

Planetary nebulae present a fascinating range of shapes and morphologies. They are ideal laboratories for the study of different astrophysical processes: atomic physics, radiative transfer, stellar winds, shocks, wind-wind interaction, and the interaction between stellar winds and the interstellar medium. In addition, planetary nebulae provide information about the late stages of stellar evolution. In the last five years studies of planetary nebulae have progressed very rapidly and new phenomena and insights have been gained. This is partly due to new observations (e.g. from the Hubble Space Telescope, the ISO satellite and new infrared and millimeter spectrographs) and partly to the advancement of hydrodynamic simulations of the structures of planetary nebulae (PN). Many of these new results were reported at IAU Symposium 180 in Groningen, the Netherlands, on August 26 to 30, 1996. This symposium was dedicated to one of the pioneers of PN research: Stuart Pottasch. These proceedings contain chapters on: Introduction to PN with the basic parameters Distances of PN The central stars of PN The envelopes of PN The evolution from AGB to PN The evolution from PN to white dwarfs PN in the galactic context PN in extragalactic systems The future of PN research . The book contains 29 reviews and more than 200 shorter contributions.

Ce volume contient les revues invitees et les presentations orales du Symposium VAl 181 Sounding Solar and Stellar Interiors, tenu a Nice du 30 septembre au 3 octobre 1996. Les posters presentes a cette conference 1 sont publies dans un volume separe. Depuis Ie lancement avec succes du satellite SoRO Ie 2 Decembre 1995, et apres des annees d'efforts importants dans Ie domaine de l'helio- et l'asterosismologie, il a semble approprie de tenir un symposium dedie aux consequences de la sismologie pour notre connaissance de la structure in- terne du Soleil et des etoiles. Le but etait de presenter a la communaute entiere les nouveaux resultats de l'heliosismologie obtenus aussi bien par les experiences spatiales que par les reseaux exist ants au sol, ainsi que les avancees theoriques dans les domaines de la structure et de la physique de l'interieur solaire. Ce but a ete largement atteint: alors que SoRO ne fournissait des don- nees que depuis environ 6 mois, la qualite des donnees heliosismologiques a ete largement amelioree, de nouvelles techniques ont ete elaborees comme la "telechronosismologie" (nom propose par D. Gough dans sa conclusion pour l'analyse temps-distance), et de nouveaux mecanismes physiques ont ete proposes pour tenter de reduire les differences persist antes entre Ie Soleil observe et les modeles standard.

Advanced technologies in astronomy at various wavelengths have provided us with high-resolution and high-quality data of the central regions of nearby galaxies and of the Milky Way Galaxy. These data, both for the Galaxy and extragalactic centers, are now quite suitable for detailed comparative study. This IAU symposium was aimed at understanding the general characteristics of dynamics, ISM physics and magnetic fields, activities including inflow and outflow, as well as starburst, in the `galactic centers'. Special attention was also given to several cases for massive black holes in galaxies and the Galaxy, and to understanding the physics of nuclei associated with black holes.

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."

Herbig-Haro objects were discovered 50 years ago, and during this half century they have developed from being mysterious small nebulae to be coming an important phenomenon in star formation. Indeed, HH flows are now recognized not only as fascinating astrophysical laboratories involving shock physics and chemistry, hydrodynamics and radiation processes, but it has gradually been realized that HH flows hold essential clues to the birth and early evolution of low mass stars. IAU Symposium No. 182 on Herbig-Haro Flows and the Birth of Low Mass Stars were held from January 20 to 24, 1997 in Chamonix in the french alps. A total of 178 researchers from 26 countries met to discuss our present level of understanding of Herbig-Haro flows and their relation to disk accretion events and T Tauri winds and other outflow phenomena like molecular outflows, embedded molecular hydrogen flows and radio jets. The present book contains the manuscripts from the oral contributions of the symposium. The poster papers were printed in a separate volume Low Mass Star Formation - from Infall to Outflow, edited by Fabien Malbet and Alain Castets, which was distributed at the beginning of the meeting. Together these two books document the vigorous state and the scientific appeal which research into Herbig-Haro flows and related issues in star formation enjoys today, observationally as well as theoretically."

There are many books on finding your way round the night sky, but the Photo-guide to the Constellations is unique in showing photographs of how the sky really looks under a variety of different seeing conditions, from city outskirts to the almost-perfect skies deep in the countryside. Along with a detailed step-by-step guide to "star hopping" and other useful techniques, these make this an invaluable guide for all newcomers to astronomy.

Starbursts are regions of unusually rapid star formation often located in the central parts of galaxies. Recent observational and theoretical developments have emphasized their importance to understand the connection between star formation, the interstellar medium, and the secular evolution of galaxies. In this book, leading experts in the field introduce the basic processes involved in the physics of starbursts, the phenomenological concepts which are used to describe and model their triggering and evolution, and their link to galaxy formation and history. A specific effort is made to start with pedagogical presentations and to review the state-of-the art of the observations and models, emphasizing the recent breakthroughs and the major issues to be explored in the future.

Interstellar carbon monoxide (CO) was first detected in 1970 with the 36 foot diameter telescope of the National Radio Astronomy Observatory on Kitt Peak in Southern Arizona. R. W. Wilson, K. B. Jefferts, and A. A. Penzias of Bell Labs reported, "We have found intense 2.6 mm line radiation 2 from nine Galactic sources which we attribute to carbon monoxide." Soon afterward, several other basic molecules were also observed in space. IAU Symposium 170, CO: Twenty Five Years of Millimeter Wave Spectroscopy, was organized to commemorate those discoveries. The Symposium reviewed the accomplishments of a quarter century of research on interstellar molec ular gas, surveyed the current state of millimeter-wave spectroscopy, and gave a glimpse of what the next 25 years might hold. Studies of interstellar CO have revolutionized our understanding of the phases and dynamics of the interstellar medium, the initial and final stages of stellar evolution, the chemistry of dense and diffuse interstellar matter and of the solar system, the structure of the Milky Way galaxy, and the content and structure of other galaxies, some very distant. Spectroscopic studies of CO and other molecules are primary tools for investigating all these topics, which are among the most fundamental and active research areas in astrophysics. New developments in instrumentation, including sev eral powerful new telescopes, continue to keep millimeter and submillimeter wavelength radio astronomy at the forefront of research."

On the 100th anniversary of Marconi's successful experiment on radio broadcasting, 250 astronomers from all over the world met in Bologna (Italy) for five days, to update their knowledge of the physics and statistical properties of powerful extragalactic radio sources. Since their discovery in the fifties enormous progress has been made. The existence of superluminal motions in the cores of radio sources, the presence there of a black hole surrounded by an absorbing dust torus, as inferred mostly from studies at other wavelengths, are now accepted ideas. Nevertheless, in spite of these efforts, there are many questions still unanswered. For instance we do not know which mechanism produces the huge amount of energy supplied to radio sources, how the jets connecting the `engine' to the lobes are formed and collimated, which of the differences observed among the various classes of radio sources are apparent and which are real. These and other related topics are discussed in this book.

This Symposium began with a proposal for a meeting to honour Emer itus Professor Robert Hanbury Brown on the occasion of his 80th birthday. He requested that any such meeting should be on a topic that would be of benefit to the Sydney University Stellar Interferometer (SUSI) program. With SUSI and several other high angular resolution instruments either in operation or coming on line within the next decade, and with advances in astrometry, spectroscopy and in theoretical models of stellar atmospheres and interiors, it appeared to be both appropriate and timely to hold a symposium on "Fundamental Stellar Properties: the Interaction between Observation and Theory. " The emphasis of the meeting was on the critical assessment of the qual ity, 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. Invited papers comprised the major part of the oral program and the speakers responded to the challenge issued by the Scientific Organising Committee to critically review the current status and prospects for their area of expertise. The Symposium was opened by the Chancellor of the University of Sydney, Emeritus Professor Dame Leonie Kramer, who welcomed the 126 participants from 22 countries on behalf of the University. The oral program included . 52 invited reviews and papers and 10 contributed papers."

This volume reviews recent progress in the study of dynamics of star clusters. The meeting focused on the enormous progress of both the observation and the theoretical modeling of star clusters. New results from the refurbished Hubble Space Telescope (HST) include the mass function down to the hydrogen burning limits, white dwarf sequence, and central density profiles of `post-collapse' clusters by star counts. On the theoretical side, this symposium saw the first direct evidence of gravothermal oscillation through N-body simulation, which was made possible by GRAPE-4, the dedicated special-purpose computer for N-body simulation. Numerical techniques to combine stellar evolution and dynamical evolution of the cluster were presented. The book will be of primary interest to astrophysicists.

In the past decade, indirect (Doppler) imaging techniques have opened up a whole new discipline in stellar astronomy, providing increasingly detailed photometric, magnetic, and chemical inhomogeneity images of stellar surfaces. Furthermore, new optical interferometers are already being used with sophisticated interferometer techniques to image stellar surface structures more directly, and in the future the ESO VLT Interferometer and other instruments will extend these capabilities enormously. These developments are highlighted in the first two sections of this book. The large number of recent results, ground-based and space-based, and the lack of a generally accepted dynamo theory with predictive power for the stars and the Sun, result in an ever-growing complexity of interpretation of individual results. The IAU Symposium 176 on Stellar Surface Structure' consequently focused on spatially resolved stellar observations throughout the H-R diagram, from O- and B-stars to late M-stars. Two further sections in this book summarize the current observational data on surface inhomogeneities in stellar photospheres, chromospheres, and coronae. Finally, a special section is devoted to next generation model atmospheres.

Jessica Khoury brings her masterful world-building and emotional depth to an exciting fantasy series. In a world where everyone is born with wings, stone monsters prowl the skies, hunting those who dare to fly too high. In the Clandoms, everyone is born with wings, with tight-knit communities formed around bird types: Jay, Falcon, Crow. Ellie Meadows dreams of growing up to join the Goldwings - the famed knights who defend all the people of the Clandoms. It was a Goldwing, after all, who saved her life on that terrible day her parents were killed. There's just one problem: Ellie is a Sparrow, and the Goldwings are almost invariably picked from the higher clans like Eagles and Ospreys. This rigid hierarchy means that Ellie is destined to become a farmer. Determined to honor her parents' memories and prove herself worthy of the Goldwings, Ellie sets out on her own for the capital. But her journey will be dangerous. Foul creatures called gargols lurk behind every cloud, ready to slay anyone unlucky enough to be caught outside in a storm - just as Ellie's family was. Soon her path intertwines with a colorful band of fellow outcasts, each with their own aspirations... and their own secrets. Ellie's new friends offer not just roadside companionship. They'll challenge her ideas of right, wrong, and what truly makes a hero. Fast-paced, highly imaginative middle grade fantasy Perfect for fans of Wings of Fire Explores important issues such as racism, classism, privilege and systemic oppression

X-ray binaries are stellar systems that combine one normal star (like our sun) and a smaller star, such as a white dwarf, a neutron star, or a black hole. This timely text provides a comprehensive overview of the unique and varied behavior of these combinations. Fifteen specially-written chapters by a team of the world's foremost researchers in the field explore all aspects of the X-ray binaries, including the X-ray, ultraviolet, optical, and radio properties of these violent systems, and address key issues such as how these systems formed and what their fate might be. They also discuss X-ray bursts and quasi-periodic oscillations, the connections between millisecond radio pulsars and low-mass X-ray binaries, and how the magnetic field of a neutron star decays. This long-awaited review provides graduate students and researchers with the standard reference on X-ray binaries for many years to come.

The study of the evolution of galaxies has made remarkable progress in recent years and is currently undergoing a transformation arising from the application of new observational and theoretical tools. Twenty-one invited reviews, twenty-six contributed papers and 137 poster papers cover the wide variety of recent developments, present new insights and demonstrate the rapid increase in our knowledge about galaxy evolution and formation.