lAD Symposium No. 66 was held in Warsaw from September 10th to September 12th 1973, in connection with the Extraordinary General Assembly of the lAD. It was arranged by lAD Symposium No. 35 and the Scientific Organising Committee con sisted of A. G. Massevitch (Chairman), A. V. Tutukov (Secretary), H. M. van Horn, N. Dallaporta, J. P. Ostriker, B. Paczynski, G. Ruben, E. Schatzman, R. J. Tayler and A. Weigert. This volume contains the full texts of all of the invited papers presented at the Symposium, apart from that delivered by R. P. Kraft, which is published in abstract because it is appearing in full elsewhere. In addition the short communications given at the Symposium are published in abstract. I attempted to take down all of the dis cussion as it occurred and all contributors to the discussion were asked to provide copies of their remarks. From these sources an edited version of the discussion has been produced. As the final version has not been seen by the contributors, I should be held responsible for all errors. At Warsaw, some of the short communications did not immediately follow the invited paper to which they referred. In the printed version they and any discussion relating to them are placed in the most logical position. A small number of short communications, which were circulated in abstract at Warsaw but which were not delivered orally, are also included in the published version.

'Understanding Stellar Evolution' is based on a series of graduate-level courses taught at the University of Washington since 2004, and is written for physics and astronomy students and for anyone with a physics background who is interested in stars. It describes the structure and evolution of stars, with emphasis on the basic physical principles and the interplay between the different processes inside stars such as nuclear reactions, energy transport, chemical mixing, pulsation, mass loss, and rotation. Based on these principles, the evolution of low- and high-mass stars is explained from their formation to their death. In addition to homework exercises for each chapter, the text contains a large number of questions that are meant to stimulate the understanding of the physical principles. An extensive set of accompanying lecture slides is available for teachers in both Keynote(R) and PowerPoint(R) formats.

Over the last decade we have witnessed a rapid change in our understanding of the late stages of stellar evolution. A major stimulus to this has been the synthesis of observational data from different wavebands of the electromagnetic spectrum. The advent of infrared astronomy has led to the discovery of many luminous. late-type stars obscured by their circumstellar dust envelope. Sources discovered in the IRC and AFGL infrared sky surveys were followed up by radio observa tions, leading to the widespread use of the OH and CO molecules as probes of the circumstellar envelopes. Advances in the technique of aperture synthesis have made possible observations with unprecedent resolving power, both in spectral-line and continuum. The success of the recent IRAS sky survey, with the detection of over 250,000 sources, brings the promise of even more exciting years ahead. This area of astronomical research is also blessed with the close collaboration between theorists and observers. New ideas are constantly being quantitatively tested by new data. Theoretical predictions are eagerly used as guides for further observations. This conference was initiated with the following objective: bring together workers in optical, infrared, radio and theoretical astronomy and let them confront each other. Based on the post-conference res ponses we received, many of the participants have indeed found this Workshop a stimulating experience. The Workshop on the Late Stages of Stellar Evolution was held from 2-5 June 1986 in Calgary, Canada.

In the last throes of their lives, how do low- and high-mass stars interact with their immediate surroundings? How does the circumstellar medium affect the shape of a nebula? How are supernovae effected by a dense medium? And what do we understand of how stellar winds interact with their environments? These and many other exciting issues are addressed in these proceedings, from the 34th Herstmonceux conference, held in Cambridge. Highlights of developments in the field covered in this volume include the latest observational results that show how various types of stellar ejecta differ in shape, and a unified view of the physical processes involved; as well as the latest results on the media around supernovae 1987A and 1993J. This timely volume provides review articles that serve both as an excellent introduction for graduate students, and a handy reference for researchers; and up-to-date research papers for those who want to keep abreast of developments in the field.

In 1965 Fritz Zwicky proposed a class of supernovae that he called "Type V", described as "excessively faint at maximum". There were only two members, SN1961v and Eta Carinae. We now know that Eta Carinae was not a true supernova, but if it were observed today in a distant galaxy we would call it a "supernova impostor". 170 years ago it experienced a "great eruption" lasting 20 years, expelling 10 solar masses or more, and survived. Eta Carinae is now acknowledged as the most massive, most luminous star in our region of the Galaxy, and it may be our only example of a very massive star in a pre-supernova state. In this book the editors and contributing authors review its remarkable history, physical state of the star and its ejecta, and its continuing instability. Chapters also include its relation to other massive, unstable stars, the massive star progenitors of supernovae, and the "first" stars in the Universe.

Driven by discoveries, and enabled by leaps in technology and imagination, our understanding of the universe has changed dramatically during the course of the last few decades. The fields of astronomy and astrophysics are making new connections to physics, chemistry, biology, and computer science. Based on a broad and comprehensive survey of scientific opportunities, infrastructure, and organization in a national and international context, New Worlds, New Horizons in Astronomy and Astrophysics outlines a plan for ground- and space- based astronomy and astrophysics for the decade of the 2010's. Realizing these scientific opportunities is contingent upon maintaining and strengthening the foundations of the research enterprise including technological development, theory, computation and data handling, laboratory experiments, and human resources. New Worlds, New Horizons in Astronomy and Astrophysics proposes enhancing innovative but moderate-cost programs in space and on the ground that will enable the community to respond rapidly and flexibly to new scientific discoveries. The book recommends beginning construction on survey telescopes in space and on the ground to investigate the nature of dark energy, as well as the next generation of large ground-based giant optical telescopes and a new class of space-based gravitational observatory to observe the merging of distant black holes and precisely test theories of gravity. New Worlds, New Horizons in Astronomy and Astrophysics recommends a balanced and executable program that will support research surrounding the most profound questions about the cosmos. The discoveries ahead will facilitate the search for habitable planets, shed light on dark energy and dark matter, and aid our understanding of the history of the universe and how the earliest stars and galaxies formed. The book is a useful resource for agencies supporting the field of astronomy and astrophysics, the Congressional committees with jurisdiction over those agencies, the scientific community, and the public.

An ideal bridging text for astrophysics and physics majors looking to move on from the introductory texts.