Quasars, and the menagerie of other galaxies with "unusual nuclei," now collectively known as Active Galactic Nuclei or AGN, have, in one form or another, sparked the interest of astronomers for over 60 years. The only known mechanism that can explain the staggering amounts of energy emitted by the innermost regions of these systems is gravitational energy release by matter falling towards a supermassive black hole --- a black hole whose mass is millions to billions of times the mass of our Sun. AGN emit radiation at all wavelengths. X-rays originating at a distance of a few times the event horizon of the black hole are the emissions closest to the black hole that we can detect; thus, X-rays directly reveal the presence of active supermassive black holes. Oftentimes, however, the supermassive black holes that lie at the centers of AGN are cocooned in gas and dust that absorb the emitted low energy X-rays and the optical and ultraviolet light, hiding the black hole from view at these wavelengths. Until recently, this low-energy absorption presented a major obstacle in observational efforts to map the accretion history of the universe. In 1999 and 2000, the launches of the Chandra and XMM-Newton X-ray Observatories finally broke the impasse. The impact of these observatories on X-ray astronomy is similar to the impact that the Hubble Space Telescope had on optical astronomy. The astounding new data from these observatories have enabled astronomers to make enormous advances in their understanding of when accretion occurs."

A quantitative measure of the accuracy of the rate coefficients and the excess energies is a desirable goal of this analysis. There are two major sources of uncertainties: The atomic and molecular data and the solar irradiance. The cross sections and branching ratios used in this analysis come from many different sources; many of them without any error indications. For this reason, we must confine ourselves to a qualitative indication of the reliability of the results. Specifically we give a quality scale in Table II for the data of each mother molecule; A indicating the highest quality of atomic and molecular data and F the lowest quality. The letter B typically means that the threshold is uncertain. For most molecules the cross section at threshold is very small and the rate coefficient for these molecules is therefore not influenced by this uncertainty. For atomic species the cross section is usually large near threshold, but for these species the threshold is known quite accurately. The letter B, therefore, indicates that the rate coefficient is most likely quite accurate, but the excess energy is less accurately known. The letter C usually means that the branching ratios are not well known. This means that the total rate coefficient is very good, but the rate coefficients and the excess energies for the individual branches are less accurate.

We stand at the threshold of an exciting era of Asteroseismology. In a few months' time, the Canadian small-satellite asteroseismology mission MOST will be laun ched. Danish and French missions MONS and COROT should follow, with the ESA mission Eddington following in 2007/8. Helioseismology has proved spec tacularly successful in imaging the internal structure and dynamics of the Sun and probing the physics of the solar interior. Ground-based observations have detected solar-like oscillations on alpha Centauri A and other Sun-like stars, and diagnostics similar to those used in helioseismology are now being used to test and constrain the physics and evolutionary state of these stars. Multi-mode oscillations are being observed in an abundance of other stars, including slowly pulsating B stars (SPB stars), delta Scuti stars, Ap stars and the pulsating white dwarfs. New classes of pulsators continue to be discovered across the Hertzsprung-Russell diagram. For good reason it was decided to entitle our conference 'Asteroseismology Across the HR Diagram' . Yet the challenges still to be faced to make asteroseismology across the HR diagram a reality are formidable. Observation, data analysis and theory all pose hard problems to be overcome. In conceiving this meeting, the aim of the organisers was to facilitate a cross-fertilization of ideas and approaches between researchers working on different pulsators and with different areas of expertise. We venture to suggest that in this the conference was a great success."

This current updated and expanded text reflects the large number of scientific advances, both theoretically and experimentally, within the discipline of cosmoparticle physics in the last 10 years. Some of the topics that have been added, updated include but are not limited to; HND or CMD+HND scenarios being implemented into sterile neutrino scenarios, the ramifications of extending the forms of dark matter with respect to our view of neutrinos, the origin of baryon matter and the need for non-baryonic matter in current theories, problems the existence of dark matters raises with respect to cosmoparticle physics and the relationship with (meta) stable (super) weakly interacting particles predicted by the extension of the standard model, restrictions on baryon and lepton photons, as well as problems associated with cosmological expansion just to name a few. These and many other topics are readdressed in light of recent both experimental and theoretical developments. Other areas of that will be of interest to the reader include the puzzles presented by direct and indirect effects of dark matter (e.g, results of experiments such as DAMA/NaI, DAMA/LIBRA and PAMELA) may lead to nontrivial new solutions for the problem of its nature, like the existence of new stable families of quarks and leptons and composite dark matter scenario. The present work will be of interest to any researcher interested in this fascinating field dealing with ""fundamental interactions of the micro- and macroworld. "

1. Data from the ROSAT Observatory. 2. The EXOSAT Database System. 3. IRAS. 4. Databases from Cosmic Background Explorer (COBE). 5. The Many faces of the Archive of the International Ultraviolet Explorer Satellite. 6. Data Archive System for the Hubble Space Telescope. 7. Database Aspects of the Guide Star Catalog. 8. The HIPPARCOS INCA Database. 9. The SIMBAD Astronomical Database. 10. The NASA/IPAC Extragalactic Database. 11. The ESO Archive Project. 12. Archives of the Isaac Newton Group, La Palma and Westerbork Observatories. 13. Archiving at NRAO's VLA and VLBA Telescopes. 14. ESIS A Science Information System. 15. The NASA Astrophysics Data System. 16. The NSSDC Services. 17. The Space Data Centre at RAL. 18. Database Applications in Starlink. 19. Database Applications in Astronet. 20. Database Services at the Canadian Astronomy Data Centre. 21. Astronomical Bibliography from Commercial Databases. 22. Astronomical Directories. 23. Science Networks: A Short Overview. 24. User Interfaces in Astronomy. 25. The FITS Data Format. List of Acronyms. Index.

The accretion process is thought to play a key role in the Universe. This book explains, in a form intelligible to graduate students, its relation to the formation of new stars, to the energy release in compact objects and to the formation of black holes. The monograph describes how accretion processes are related to the presence of jets in stellar objects and active galactic nuclei and to jet formation. The authors treat theoretical work as well as current observational facts. This volume of the highly esteemed Les Houches series is meant as an advanced text that can serve to attract students to exciting new research work in astrophysics.

Since its launch in 1991, the Yohkoh satellite has been returning unprecedented observations of solar flares and the dynamic solar corona. This book is a collection of papers presented at a meeting held in: Yoyogi, Tokyo, on the occasion of Yohkoh's fifth anniversary of operation. The papers constitute a summary of observations and results over the five years, including contributions based on data from Yohkoh's hard and soft X-ray telescopes and its spectrometer experiments. The five years of data, covering approximately one-half of a solar cycle, reveal a fresh perspective on solar science, with a new picture of solar flares and the active Sun emerging. Also, for the first time there are extensive results from Yohkoh observations of the Sun during the solar minimum period. This wide-ranging volume will be of interest to workers in solar physics and X-ray astronomy. It also contains material appropriate for supplemental reading for graduate students in solar physics.

This textbook is for mathematicians and mathematical physicists and is mainly concerned with the physical justification of both the mathematical framework and the foundations of the theory of general relativity. Previous knowledge of the relevant physics is not assumed. This book is also suitable as an introduction to pseudo-Riemannian geometry with emphasis on geometrical concepts. A significant part of the text is devoted to the discussion of causality and singularity theorems. The insights obtained are applied to black hole astrophysics, thereby making the connection to current active research in mathematical physics and cosmology.

While the emergence and evolution of solar surface magnetic flux reveals what goes on in the solar interior, the interplay of convection and magnetic field in the photosphere regulates the field dispersal and drives the instabilities which heat the outer solar atmosphere. This book presents a synthesis between observers and theorists, both with regard to the magnetic elements which make up solar magnetic fields (ranging from tiny flux tubes to whole active regions), and to the surface patterns in which these elements display properties of the subsurface dynamo. A major breakthrough comes from numerical simulations. Modelling of flux concentration, flux tube dynamics, penumbral toplogy, umbral fine structure, and so on, turns solar physics into an experimental science. The reviews and research papers in this volume provide an overview of the solar frontier of astrophysical magnetohydrodynamics. The elements and patterns of solar surface magnetism contain much information about the subsurface solar dynamo, as well as on the magnetically-dominated energy budget and structuring of the outer solar atmosphere. The volume treats high-resolution solar polarimetry, the physics of solar magnetic elements, and the information contained in their patterns of emergence on the solar surface in depth, with a balance between theoretical and observational studies.

Dramatic progress is a trademark of the recent study of globular cluster systems. Considerations about the formation and evolution compose the first chapter, followed by a chapter on young star clusters. Then come four chapters reviewing the globular cluster system of early-type, late-type and dwarf galaxies, as well as of groups of galaxies. One chapter is dedicated to stellar population models and their applications to the field. Finally a chapter reviews the kinematics of galaxies derived from globular cluster systems and another their role in the context of galaxy formation and evolution studies. As a whole, the book gives an up-to-date view of the field at the beginning of the new decade, which will without doubt again bring significant progress in our understanding of globular cluster systems and galaxy formation and evolution.

In this short book, renowned theoretical physicist and author Carlo Rovelli gives a straightforward introduction to Einstein's General Relativity, our current theory of gravitation. Focusing on conceptual clarity, he derives all the basic results in the simplest way, taking care to explain the physical, philosophical and mathematical ideas at the heart of "the most beautiful of all scientific theories". Some of the main applications of General Relativity are also explored, for example, black holes, gravitational waves and cosmology, and the book concludes with a brief introduction to quantum gravity. Written by an author well known for the clarity of his presentation of scientific ideas, this concise book will appeal to university students looking to improve their understanding of the principal concepts, as well as science-literate readers who are curious about the real theory of General Relativity, at a level beyond a popular science treatment.

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.

This volume documents the contributions presented at the III Scientific Meeting of the Spanish Astronomical Society (SEA). Covering a wide range of topics, the 92 contributed papers give a comprehensive overview of the current state of Spanish astronomy. The Proceedings include special reviews dealing with the cosmological evolution of star-forming galaxies, the nature of cosmic gamma-ray bursts, infrared astrophysics with ISO, and the distance scale after Hipparcos, with special emphasis on the development of the next generation of instruments to propel astrophysical research into the new century. The contents of these Proceedings thus reflect the broad interests of the Spanish astronomical community. The significance of these proceedings can hardly be exaggerated, since here, for the first time, the SEA publishes the proceedings of its own scientific meeting. The intended audience is professional astronomers and graduate astronomy students worldwide.

Many of the ISO observers who assembled for this workshop at Ringberg c- tle met for the third time in the Bavarian Alps. At two previous meetings in 1989 and 1990 surveys were only a minor topic. At that time we were excited by the discoveries of the IRAS survey mission and wanted to follow it up with pointed observations using an observatory telescope equipped with versatile instruments. With the rapid development of detector arrays and stimulated by ISO's Observing Time Allocation Committee, however, surveys eventually became an issue for the upcoming mission. In a review paper on "Infrared S- veys - the Golden Age of Exploration" given at an IAU meeting in 1996, Chas Beichman already mentioned that there are ISO surveys. They were at the bottom of his hit list, while the winners were future space missions (Planck, SIRTF, etc. ) and ground-based surveys in preparation (Sloan, 2MASS, DE- NIS, etc. ). He organized his table according to the relative explorable volume, calculated from the solid angle covered on the sky and the maximum distance derived from the detection sensitivity. Clearly, with this ?gure of merit, ISO, as a pointed observatory, is rated low. Applying the classical de?nition of a survey, i. e. to search in as large a volume as possible for new or rare objects and/or study large numbers of objects of various classes in order to obtain statistical properties, ISO was indeed limited.

The systematic study of the planets has experienced a slow but steady progress from the efforts of a single individual (Galileo Galilei, 1564-1642) to nations that individually and collectively create whole agencies and complex infrastructures devoted to the exploration and understanding of our solar system. This quest for knowledge continues in earnest today as we attempt to understand Earth's unique place among its closest neighbors. Known diversities emphasize fractionation processes that may have occurred in the nebula during early solar system formation, and the vastly different evolutionary paths taken by the planets and their satellites. The discovery of similarities and differences among the planets has given rise to a discipline of "Comparative Planetology. " Here terrestrial properties and giant planet atmospheres are viewed and probed, surface geologies are related to atmospheres and oceans, interior structures are envisioned, magnetic fields mapped, and bizarre differences in satellites and ring systems continue to enlighten, amaze and confound the detectives of planetary science. A science organizing committee with international participation was formed to develop a conference program to address the basic issues and the fundamental processes that are common among the planets. The goals of the meeting were twofold: first the production of a reference source on comparative planetology for academia, and second, the provision of an impetus for NASA to begin a program devoted to this emerging science discipline. The conference program accommodated seventeen invited papers and nineteen poster presentations.

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

This Atlas provides a complete set of images of Local Group Galaxies (excluding the three for which identification atlases are already in print) and shows the most important objects, including many thousands of individual stars and interstellar objects.

It is unique in its coverage and format and provides a source of these fundamental data that will be used for many years. Researchers, students and even amateur astronomers will be able to use the Atlas to identify and study the various components of the nearly 30 important galaxies covered by the Atlas.

The objects identified on the more than 200 charts include variable stars, globular star clusters, open star clusters, stellar associations, emission regions, supernova remnants, planetary nebulae and dust clouds. Each galaxy is accompanied by an extensive bibliography.

A Corotating Interaction Region (CIR) is the result of the interaction of fast solar wind with slower solar wind ahead. CIRs have a very large three-dimensional ex tent and are the dominant large-scale structure in the heliosphere on the declining and minimum phase of the solar activity cycle. Until recently, however, CIRs could only be observed close to the ecliptic plane, and their three-dimensional structure was therefore not obvious to observers and theoreticians alike. Ulysses was the first spacecraft allowing direct exploration of the third dimen sion of the heliosphere. Since 1992, when it has entered a polar orbit that takes it 0 up to 80 latitude, the spacecraft's performance has been flawless and the mission has provided excellent data from a superbly matched set of instruments. Perhaps the most exciting observation during Ulysses' first passage towards the south pole of the Sun was a strong and long lasting CIR whose energetic particle effects were observed up to unexpectedly high latitudes. These observations, documented in a number of publications, stimulated considerable new theoretical work.

This textbook presents the established sciences of optical, infrared, and radio astronomy as distinct research areas, focusing on the science targets and the constraints that they place on instrumentation in the different domains. It aims to bridge the gap between specialized books and practical texts, presenting the state of the art in different techniques. For each type of astronomy, the discussion proceeds from the orders of magnitude for observable quantities that drive the building of instrumentation and the development of advanced techniques. The specific telescopes and detectors are then presented, together with the techniques used to measure fluxes and spectra. Finally, the instruments and their limits are discussed to assist readers in choice of setup, planning and execution of observations, and data reduction. The volume also includes worked examples and problem sets to improve student understanding; tables and figures in chapters su mmarize the state of the art of instrumentation and techniques.

This volume is written by leading scientists in the field, who review the current state of our knowledge of tidal streams in the Milky Way, the Andromeda galaxy, and in other nearby galaxies. The cosmological origins of dwarf galaxies and the physical processes by which they are tidally disrupted into streams and incorporated into galaxy halos are discussed. The techniques that have been used to identify tidal streams are presented and will be useful to researchers who would like to find substructures in the next generation of optical sky surveys, including Pan-STARRS and LSST. The methods that are currently under development to constrain both large scale distribution of dark matter in the Milky Way and the (small scale) lumpiness of the dark matter distribution are also explained. The authors also provide motivation for future spectroscopic surveys of Milky Way halo stars, which will aid both in the identification of tidal streams and the constraint of dark matter properties. This volume is aimed at graduate students who are beginning this field of research, but is also a resource for researchers who study tidal streams and related fields. In addition to presenting the physical processes by which tidal streams are created, it also reviews the current state of the observations and the progress towards utilizing these observations to constrain the distribution of dark matter in the Milky Way. The book will introduce anyone with a background in astrophysics to the field of tidal streams.

Magnetic fields are responsible for much of the variability and structuring in the universe, but only on the Sun can the basic magnetic field related processes be explored in detail. While several excellent textbooks have established a diagnostic foundation for exploring the physics of unmagnetized stellar atmospheres through spectral analysis, no corresponding treatise for magnetized stellar atmospheres has been available. The present monograph fills this gap. The theoretical foundation for the diagnostics of stellar magnetism is developed from first principles in a comprehensive way, both within the frameworks of classical physics and quantum field theory, together with a presentation of the various solar applications. This textbook can serve as an introduction to solar and stellar magnetism for astronomers and physicists at the graduate or advanced undergraduate level and will also become a resource book for more senior scientists with a general interest in cosmic magnetic fields.

Galaxies and Chaos examines the application of tools developed for Nonlinear Dynamical Systems to Galactic Dynamics and Galaxy Formation, as well as to related issues in Celestial Mechanics. The contributions collected in this volume have emerged from selected presentations at a workshop on this topic and key chapters have been suitably expanded in order to be accessible to nonspecialist researchers and postgraduate students wishing to enter this exciting field of research.

Ground- or space-based telescopes are becoming increasingly more complex and construction budgets are typically in the billion dollar range. Facing costs of this magnitude, availability of engineering tools for prediction of performance and design optimization is imperative. Establishment of simulation models combining different technical disciplines such as Structural Dynamics, Control Engineering, Optics and Thermal Engineering is indispensable. Such models are normally called Integrated Models because they involve many different disciplines. The models will play an increasingly larger role for design of future interdisciplinary optical systems in space or on ground. The book concentrates on integrated modeling of optical and radio telescopes but the techniques presented will be applicable to a large variety of systems. Hence, the book will be of interest to optical and radio telescope designers, designers of spacecrafts that include optical systems, and to designers of various complex defense systems. The book may also find use as a textbook for undergraduate and graduate courses within the field. "Adaptive Optics" is an exciting and relatively new field, originally dedicated to correction for blurring when imaging through the atmosphere. Although this objective is still of high importance, the concept of Adaptive Optics has recently evolved further. Today, the objective is not only to correct for atmospheric turbulence effects but also for a range of static and dynamical telescope aberrations. The notion of adaptive optics has expanded to the field of "Wavefront Control", correcting for a variety of system aberrations. Wavefront control systems maintain form and position of optical elements with high precision under static and dynamical load. In many ways, such systems replace the steel structures of traditional optical systems, thereby providing much lighter systems with a performance not possible before. Integrated Modeling is the foremost tool for studies of Wavefront Control for telescopes and complex optics and is therefore now of high importance. Springer has recently published two books on telescopes, "Reflecting Telescope Optics" by R. Wilson, and "The Design and Construction of Large Optical Telescopes" by P. Bely. Noting that a new (and expensive) generation of Extremely Large Telescopes with apertures in the 30-100 m range is on the way, the present book on integrated modeling is a good match to the existing books and an appropriate specialization and continuation of some subjects dealt with in those books.

The aim of the inaugural meeting of the Sant Cugat Forum on Astrophysics was to address, in a global context, the current understanding of and challenges in high-energy emissions from isolated and non-isolated neutron stars, and to confront the theoretical picture with observations of both the Fermi satellite and the currently operating ground-based Cherenkov telescopes. Participants have also discussed the prospects for possible observations with planned instruments across the multi-wavelength spectrum (e.g. SKA, LOFAR, E-VLT, IXO, CTA) and how they will impact our theoretical understanding of these systems.
In keeping with the goals of the Forum, this book not only represents the proceedings of the meeting, but also a reflection on the state-of-the-art in the topic.