Solar Physics publishes up to two Topical Issues per year that focus on areas of especially vigorous and active research. The present Topical Issue contains papers 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 with the standards of Solar Physics, were presented in August 1999 at a workshop held in Monterey, California. The authors were offered the opportunity to present relevant parts of their contributions on an accompanying CD ROM of this Topical Issue. The Sun's magnetic field is responsible for the spectacularly dynamic and intri cate phenomenon that 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 satellite has observed the Sun now for over eight years, producing spectac ular sequences of images that convey the complexity of the corona. The imaging and spectroscopic instruments on SOHO have added information on the cooler part of the corona. And since April of 1998 TRACE has given us very high resolution images of the 1-2 MK corona, at cadences that allow detailed observations of field oscillations, loop evolution, mass ejecta, etc.

IAU Transactions are published as a volume corresponding to each General Assembly.

Volume A is produced prior to the Assembly and contains Reports on Astronomy, prepared by each Commission President. The intention is to summarize the astronomical results that have affected the work of the Commission since the production of the previous Reports up to a time which is about one year prior to the General Assembly.

Volume B is produced after the Assembly and contains accounts of Commission Meetings which were held, together with other material. The reports included in the present volume range from outline summaries to lengthy compilations and references.

This volume presents an analysis of the historical background, current status, and future development of space law by noted legal scholars. It focuses on a distinct and growing field of international law that incorporates both public and private law. Specific areas covered are scientific and technical aspects of space and space law; the United Nations and other institutional arrangements; national regulatory aspects; satellite applications; commercialization; dispute settlement; and case law.

Since the establishment of a special law-making body at the United Nations in 1958, there has been a steady expansion of laws and regulations pertaining to space activities. The result has been the development of a distinct and mature discipline of international law. This analysis of space law by recognized experts in the field will interest scholars, practitioners, and policy-makers involved in the regulation of space use and exploration.

Viewed as a flashpoint of the Scientific Revolution, early modern astronomy witnessed a virtual explosion of ideas about the nature and structure of the world. This study explores these theories in a variety of intellectual settings, challenging our view of modern science as a straightforward successor to Aristotelian natural philosophy. It shows how astronomers dealt with celestial novelties by deploying old ideas in new ways and identifying more subtle notions of cosmic rationality. Beginning with the celestial spheres of Peurbach and ending with the evolutionary implications of the new star Mira Ceti, it surveys a pivotal phase in our understanding of the universe as a place of constant change that confirmed deeper patterns of cosmic order and stability.

The idea of having a conference in Padova describing the results obtained by the Galileo spacecraft and the characteristics of the Telescopio Nazionale Galileo began in 1995, when a number of colleagues from both sides of the Atlantic began exchanging suggestions and ideas. Looking at the schedules of the two teams, it was clear that the beginning of January 1997 would be a good time to hold the conference; these dates also luckily coincided with the dates of the memorable discovery of the Medicean moons of Jupiter by Galileo Galilei in Padova in 1610. To emphasize these three elements, the name of the conference was then proposed and accepted by the involved parties: NASA and JPL in the United States, the German space agency DARA, the University of Padova, and the Astronomical Observatory in Padova. I wish to recall a few key dates: In January 1610, Galileo--from his house in Padova--had the first hint of three and then four stars connected to Jupiter. In December 1995, the probe released from the spacecraft entered the atmosphere of Jupiter, and the spacecraft entered orbit about Jupiter. These extraordinary events were followed at JPL by a number of representatives of many institutions and space agencies. In June 1996, the Telescopio Nazionale Galileo was inaugurated by the King of Spain Juan Carlos I, in the presence of Prof. Luigi Berlinguer, Minister of University and Science. These ceremonies occurred as the spacecraft started touring the moon Europa.

The Encyclopedia of Cosmology, first published in 1993, recounts the history, philosophical assumptions, methodological ambiguities, and human struggles that have influenced the various responses to the basic questions of cosmology through the ages, as well as referencing important scientific theories. Just as the recognition of social conventions in other cultures can lead to a more productive perspective on our own behaviour, so too a study of the cosmologies of other times and places can enable us recognise elements of our own cosmology that might otherwise pass as inevitable developments. Apart from modern natural science, therefore, this volume incorporates brief treatments of Native American, Cave-Dweller, Chinese, Egyptian, Islamic, Megalithic, Mesopotamian, Greek, Medieval and Copernican cosmology, leading to an appreciation of cosmology as an intellectual creation, not merely a collection of facts. It is a valuable reference tool for any student or academic with an interest in the history of science and cosmology specifically.

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.

This volume comprises nine articles on Islamic astronomy published since 1989 by Benno van Dalen. Van Dalen was the first historian of Islamic astronomy who made full use of the new possibilities of computers in the early 1990s. He implemented various statistical and numerical methods that can be used to determine the mathematical properties of medieval astronomical tables, and utilized these to obtain entirely new, until then unattainable historical results concerning the interdependence of individual tables and hence of entire astronomical works. His programmes for analysing tables, making sexagesimal calculations and converting calendar dates continue to be widely used. The five articles in the first part of this collection explain the principles of a range of statistical methods for determining unknown parameter values underlying astronomical tables and present extensive step-by-step examples for their use. The four articles in the second part provide extensive studies of materials in unpublished primary sources on Islamic astronomy that heavily depend on these methods. The volume is completed with a detailed index.

This thesis by Cole Johnston brings novel insights into the inner workings of young massive stars. By bridging the observational fields of binary stars and asteroseismology this thesis uses state of the art statistical techniques to scrutinise theories of modern stellar astrophysics. Developing upon the commonly used isochrone fitting methodology, the author introduces the idea of isochrone cloud fitting in order to account for the full breadth of physics observed in stars. The author combines this methodology with gravity mode asteroseismic analysis to asses the level of chemical mixing deep within the stellar core in order to determine the star's age and core mass. Wrapped into a robust statistical framework to account for correlations, this methodology is employed to analyse individual stars, multiple systems, and clusters alike to demonstrate that chemical mixing has dramatic impact on stellar structure and evolution.

It was about fourteen years ago that some of us became intrigued with the idea of searching the sky for X-ray and gamma-ray sources other than the Sun, the only celestial emitter of high-energy photons known at that time. It was, of course, clear that an effort in this direction would not have been successful unless there occurred, somewhere in space, processes capable of producing high-energy photons much more efficiently than the processes responsible for the radiative emission of the Sun or of ordinary stars. The possible existence of such processes became the subject of much study and discussion. As an important part of this activity, I wish to recall a one-day conference on X-ray astronomy held at the Smithsonian Astrophysical Observatory in 1960. The theoretical predictions did not provide much encouragement. While several 'unusual' celestial objects were pin-pointed as possible, or even likely, sources of X-rays, it did not look as if any of them would be strong enough to be observable with instru mentation not too far beyond the state of the art. Fortunately, we did not allow our selves to be dissuaded. As far as I am personally concerned, I must admit that my main motivation for pressing forward was a deep-seated faith in the boundless re sourcefulness of nature, which so often leaves the most daring imagination of man far behind."

How old is our Universe? At what speed is our Universe expanding? Is our universe flat or curved? How is the hierarchical structure of the present Universe formed? The purpose of IAU Symposium 183 on the Cosmological Parameters and the Evolution of the Universe was to encourage a state-of-the-art discussion and assessment of cosmology by putting together the latest observational data and theoretical ideas on the evolution of the universe and cosmological parameters. In this volume, excellent reviews on these subjects by distinguished scientists are included. The first article by M.S. Longair, Cosmological Parameters and the Evolution of the Universe: Progress and Prospect', is a magnificent general review which can be understood by non-specialists. The other reviews include Hubble Constants (W.L. Freedman, G.A. Tammann), Microwave Background Radiation (R.B. Partridge, N. Sugiyama), Galaxy Formation and Evolution (R.S. Ellis) and Alternative Cosmological Models (J.V. Narlikar). In addition to the reviews, recent observational and theoretical developments by outstanding active scientists are included.

This translation of"A Brief History of Radio Astronomy in the USSR"makes descriptions of the antennas and instrumentation used in the USSR, the astronomical discoveries, as well as interesting personal backgrounds of many of the early key players in Soviet radio astronomy available in the English language for the first time. This book is a collection of memoirs recounting an interesting but largely still dark era of Soviet astronomy. The arrangement of the essays is determined primarily by the time when radio astronomy studies began at the institutions involved. These include the Lebedev Physical Institute (FIAN), Gorkii State University and the affiliated Physical-Technical Institute (GIFTI), Moscow State University Sternberg Astronomical institute (GAISH) and Space Research Institute (IKI), the Department of Radio Astronomy of the Main Astronomical Observatory in Pulkovo (GAO), Special Astrophysical Observatory (SAO), Byurakan Astrophysical Observatory (BAO), Crimean Astrophysical Observatory, Academy of Sciences of the Ukraine (SSR), Institute of Radio Physics and Electronics of the USSR Academy of Sciences (IRE), Institute of Terrestrial Magnetism, the Ionosphere and Radio-Wave Propagation Institute (IZMIRAN), Siberian Institute of Terrestrial Magnetism, the Ionosphere and Radio-Wave Propagation (SibIZMIRAN), the Radio Astrophysical Observatory of the Latvian Academy of Sciences and Leningrad State University.

"A Brief History of Radio Astronomy in the USSR"is a fascinating source of information on a past era of scientific culture and fields of research including the Soviet SETI activities. Anyone interested in the recent history of science will enjoy reading this volume.

"

This NATO Advanced Study Institute provided an up dated 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 structure, dark matter problem, and the interplay between them. The focus was placed on the Cosmic Microwave Background Radiation. Emphasis was given to the mutual impact of fundamental physics and cosmology, both at theoretical 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. Special Lectures were devoted to neutrinos in astrophysics and high energy astrophysics. In addition, each Course of this series, introduced and promoted topics or subjects, which, although not being of purely astrophysical or cosmological nature, were of relevant physical interest for astrophysics and cosmology. Deep understanding, clarification, synthesis, careful interdisciplinarity within a fundamental physics framework, werethe maingoals ofthe course. Lectures ranged from a motivation and pedagogical introduction for students and participants not directly working in the field to the latest developmentsand most recent results. All Lectures were plenary, had the same duration and were followed by a discussion. The Course brought together experimentalists and theoretical physicists, astrophysicists and astronomers from a variety of backgrounds, including young scientists at post-doctoral level, senior scientists and advanced graduatestudentsas well.

This text expounds in a logical and scientific manner the idea that life did not originate on earth, but was added to it from the comets. When Fred Hoyle and Chandra Wickramasinghe first made this proposal in the 1970s, they had few takers - because the theory flew in the face of established beliefs. This text argues that in recent years, evidence to support this theory has accumulated from many different directions and grown to the point of being compelling. This work should be of value to readers interested in general science, the origin of man and the meaning of life.

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

Proceedings of the 85th Symposium on the International Astronomical Union held in Victoria, B.C., Canada, August 27-30, 1979

The Symposium on Infrared and Submillimeter Astronomy was held in Philadelphia, Pennsylvania, U.S.A., on June 8-10, 1976, as an activity associated with the Nineteenth Plenary Meeting of the Committee on Space Research (CaSPAR). The Symposium was sponsored jointly by CaSPAR, the International Astronomical Union (IAU) and the International Union of Radio Science CURSI). caSPAR is an interdisciplinary scientific organization, established by the International Council of Scientific Unions in 1958, to, in the words of its charter, "provide the world scientific community with the means whereby it may exploit the possibilities of satellites and space probes of all kinds for scientific purposes and exchange the resulting data on a co operative basis." The purpose of this particular CaSPAR Sympo sium was to present new results in infrared and submillimeter astronomy obtained by observations on aircraft, high altitude balloons, rockets, satellites, and space probes. Topics dis cussed included the Sun, the solar system, galactic and extra galactic objects as well as the cosmic background radiation. Instrumentation for observations in infrared and submillimeter astronomy was also discussed, with particular emphasis on future programs from space observatories."

Ken Freeman I would like to pick out a few items that I found particularly interesting. The choice probably reflects my ignorance, because many of these topics are no doubt more known to most of you. I am fairly sure that some of them are basic and important. We will start with the first session. There were three closely related papers on the evolution of massive stars, the formation of open clusters and associations and the IMF. We learned that clusters appear to form in initially bound clouds 6 of masses between 10'+_10 M , but star formation is a destructive process. Most of the gas is@ lost and the remaining stars then find themselves in an unbound system, which naturally disperses on a dynamical time. As a result of this, star formation is typically a fairly inefficient process, at least on the scale of open clusters. However (as Heggie pointed out) it seems to be somewhat more efficient on smaller scales, as evidenced by the fairly high incidence of binary stars. To form a bound cluster requires a higher efficiency of star formation, typically 30% or more, and we see how the three papers of this morning session relate: the initial mass function and the timing of where and when the DB stars form dictate the likely fate of the system.

The symbiosis between particles physics and cosmology has virtually become a conjugal relationship. Hence the 9th Biennial Course of the International School of Cosmic-Ray Astrophysics was designed to bridge these formerly disparate disciplines. This NATO Advanced Study Institute took place at the Ettore Majorana Centre in Erice, Italy, June 20-30, 1992. Seventy participants from 17 countries participated in lively interactions and enjoyed the stimulating lectures that form the basis for this volume. The book includes current advances in both astrophysics (cosmic gamma ravs, X-rays, cosmic rays) and cosmology (an introduction to inflation in big-bang theory, the age of the universe, nucleosynthesis in the early universe). It is suitable for reading and study by all interested physical scientists, especially those having a limited specialized background in astrophysics and cosmology.

This volume covers most areas in the physics of the solar system, with special emphasis on gravitational dynamics; its gist is the rational, in particular mathematical, understanding of the main processes at work. Special stress is given to the variety of objects in the planetary system and their long-term evolution. The unique character of this book is its breadth and depth, which aims at bringing the reader to the threshold of original research; however, special chapters and introductory sections are included for the benefit of the beginner.

Physics of the Solar System is based on the earlier work by B. Bertotti and P. Farinella: Physics of the Earth and the Solar System, which has been completely revised and updated, and more focused on the solar system. It generally attains a higher level than the previous version. This volume is generally suitable for post-graduate students and researchers in physics, especially in the field related to the solar system. A large amount of figures and diagrams is included, often compiled with real data.

Introduction to Cosmology provides a rare combination of a solid foundation of the core physical concepts of cosmology and the most recent astronomical observations. The text is designed for advanced undergraduates or beginning graduate students and assumes no prior knowledge of general relativity. An emphasis is placed on developing the students' physical insight rather than losing them with complex math. An approachable writing style and wealth of fresh and imaginative analogies from "everyday" physics are used to make the concepts of cosmology more accessible.

The symposium on "Neutral Clouds near HII Regions" was prompted by an obvious need to bring together workers specifically interested in the dynamical and photochemical effects in regions showing clear evidence of on-going star formation. This is currently an are a of considerable research activity with much new observational material over the wavelength range from X-ray to radio. Furthermore, the field isbeginning to mature. No longer is molecular spectroscopy concerned only with the search for new lines and with preliminary surveys. No longer are evolving HII regions modelled with the naive assumption of constant density. Similarly, ideas of successive star formation, "champagne" and "blister" models of HII regions, and refinements to abundance calculations are examples which show that theoretical initiative is keeping pace. We were both surprised and gratified by the number of contributed papers and the extent to which they addressed the subject matter. In the proceedings we have grouped these papers near the most appropriate of the four invited review papers. The subjects of these reviews are in the general areas of "Evolution of HII Regions," "Dynamical Interactions," "Chemistry in Active Regions" and "Infrared and Maser Sources." The symposium comprised 42 orally presented papers and 23 poster papers. AII but two are reproduced in this volume.

Classical stellar evolution theories have undergone some drastic changes in recent decades. New insights into the development of stellar interiors were obtained from studying stars in various stages of their lives, as well as with the help of fast computers, which gave a boost to the branch of numerical modelling of stellular structure and evolution. This book is divided into two parts. The first part deals with the general aspects of stellular structure and evolution including a chapter on numerical modelling. The second part deals with specific evolutionary aspects of single and binary stars with a variety of masses. The last chapter gives several models of stars with specific masses. The book is intended as an introduction for students, as well as a reference for researchers.

Short Historical Overview In the 1940s, two phenomena in the ?eld of cosmic rays (CR) forced scientists to think that the Sun is a powerful source of high-energy particles. One of these was discovered because of the daily solar variation of CR, which the maximum number of CR observed near noon (referring to the existence of continuous ?ux of CR from the direction of the Sun); this became the experimental basis of the theory that CR's originate from the Sun (or, for that matter, from within the solar system) (Alfven 1954). The second phenomenon was discovered when large ?uxes of high energy particles were detected from several solar ?ares, or solar CR. These are the - called ground level events (GLE), and were ?rst observed by ionization chambers shielded by 10 cm Pb (and detected mainly from the secondary muon-component CR that they caused) during the events of the 28th of February 1942, the 7th of March 1942, the 25th of July 1946, and the 19th of November 1949. The biggest such event was detected on the 23rd of February 1956 (see the detailed description in Chapters X and XI of Dorman, M1957). The ?rst phenomenon was investigated in detail in Dorman (M1957), by ?rst correcting experimental data on muon temperature effects and then by using coupling functions to determine the change in particle energy caused by the solar-diurnal CR variation."