Presents observational and theoretical papers from world experts addressing the important role in astrophysics of massive stars.

This book reviews the importance of massive stars in several areas of astrophysics. Massive stars are objects that are 10-100 times the mass of our Sun. Above ten solar masses, loss through stellar winds begins to have a major impact on the evolution of a star. The upper limit of 100 solar masses is derived from observations. Significant progress has now been achieved in massive star research. New models, along with high quality observations, have improved our understanding of the formation, structure, atmosphere, and evolution of these massive objects. They are formed in violent bursts of star formation and are probably related to the phenomena observed in active galactic nuclei. The workshop at the Space Telescope Science Institute examined the interplay between the astrophysics of massive stars and their location in extragalactic starburst regions. There are eighteen chapters by leading researchers. Each has been carefully edited to ensure that the book is a comprehensive introduction to the theory and observation of massive stars in starburst regions.

Massive stars occupy an exceptional place in general astrophysics. They trigger many if not all of the important processes in galactic evolution whereas due to their intrinsic brightness, they offer the (only until now) possibility to study the stellar content and stellar behaviour in distant galaxies. The last, say, 25 years, massive stars have been the subject of numerous meetings discussing the influence of massive stars on population synthesis, the number distribution of different types of massive stars, the LBV phenomenon, WR stars, X-ray binaries, stellar winds in massive stars, chemical pecularities in massive stars, supernova explosions of massive stars and the important SN1987A event, the influence of massive stars and chemical evolution of galaxies. It is clear that without a theory of stellar evolution, the study of these topics loses a lot of its significance. Massive star evolution therefore got a chance in these meetings, but rarely as a prime subject. The state of the art, the physical processes and the uncertainties in stellar evolution were barely touched. Even more, the influence of close binaries in all these massive star meetings slowly disappeared the last, say, 13 years without any scientific justification, although a significant fraction of stars occurs in close binaries with periods small enough so that both components will interact during their evolution. Denying the binaries or not discussing their influence on results and conclusions, makes the latter very uncertain or even completely unreliable.

This book presents the status of research on very massive stars in the Universe. While it has been claimed that stars with over 100 solar masses existed in the very early Universe, recent studies have also discussed the existence and deaths of stars up to 300 solar masses in the local Universe. This represents a paradigm shift for the stellar upper-mass limit, which may have major implications far beyond the field of stellar physics. The book comprises 7 chapters, which describe this discipline and provide sufficient background and introductory content for graduate (PhD) students and researchers from different branches of astronomy to be able to enter this exciting new field of very massive stars.

Reviews our current understanding of the life, evolution and death of massive stars; for researchers and graduate students.

Proceedings of a Symposium held in Dwingeloo, The Netherlands, September 24-26, 1984 in honour of Adriaan Blaauw on the occasion of his 70th birthday

The most massive stars in the galaxy - those with more than 15 to 20 solar masses - are lilkely to ionize their surroundings before they reach their final mass. How can they accrete in spite of the presence of over-pressurized gas? This thesis presents results of Submillimeter Array (SMA) and Very Large Array (VLA) studies of massive star formation regions in the early stages of ionization, as well as an analysis of numerical simulations of the evolution of these young HII regions. The results favor a picture in which very massive stars form in accretion flows that are partially ionized and that keep accreting material from their environment.