IAU S240 focuses on recent advances across the broad field of binary star research.

The Transactions XXVIIA Reports on Astronomy 2006-2009 provides a comprehensive and authoritative review of what has been achieved in astronomy during the years 2006 to 2009. These insightful and up-to-date reviews have been written by the presidents and chairpersons of the IAU scientific bodies: the Divisions, the Commissions, and the Working Groups. Topics covered in this wide-ranging volume include: fundamental astronomy; the Sun and heliosphere; planetary sciences; stars; variable stars; interstellar matter; the Galactic system; galaxies and the Universe; optical and infrared techniques; radio astronomy; space and high-energy astrophysics; and other IAU activities. The reviews have been written at a level suitable for colleagues in the same fields, but will also be useful for students and researchers wishing to gain an overview of astronomical fields beyond their own research area.

An overview is presented of the many new and exciting developments in binary and multiple star studies that were discussed at IAU Symposium 240. Impacts on binary and multiple star studies from new technologies, techniques, instruments, missions and theory are highlighted. It is crucial to study binary and multiple stars because the vast majority of stars (>60%) in our Galaxy and in other galaxies consist, not of single stars, but of double and multiple star systems. To understand galaxies we need to understand stars, but since most are members of binary and multiple star systems, we need to study and understand binary stars. The major advances in technology, instrumentation, computers, and theory have revolutionized what we know (and also don't know) about binary and multiple star systems. Data now available from interferometry (with milliarcsecond [mas] and sub-mas precisions), high-precision radial velocities (1-2 m/s) and high precision photometry (

Astronomers learn much of what they know about the mass, brightness, and size of stars by observing binary systems, in which two stars orbit each other, periodically cutting off the others light. This book provides astronomers with a guide to specifying an astrophysical model for a set of observations, selecting an algorithm to determine the parameters of the model, and estimating the errors of the parameters.

An authoritative account of the contributions to science made by the Hipparcos satellite, for astronomers, astrophysicists and cosmologists.

Binary systems of stars are as common as single stars. Stars evolve primarily by nuclear reactions in their interiors, but a star with a binary companion can also have its evolution influenced by the companion. Multiple star systems can exist stably for millions of years, but can ultimately become unstable as one star grows in radius until it engulfs another. This volume, first published in 2006, discusses the statistics of binary stars; the evolution of single stars; and several of the most important kinds of interaction between two (and even three or more) stars. Some of the interactions discussed are Roche-lobe overflow, tidal friction, gravitational radiation, magnetic activity driven by rapid rotation, stellar winds, magnetic braking and the influence of a distant third body on a close binary orbit. A series of mathematical appendices gives a concise but full account of the mathematics of these processes.

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.

Stellar Astrophysics contains a selection of high-quality papers that illustrate the progress made in research into the structure and evolution of stars. Senior undergraduates, graduates, and researchers can now be brought thoroughly up to date in this exciting and ever-developing branch of astronomy.