One of the hottest debates in astronomy and cosmology today concerns the value of the Hubble constant. This constant is of paramount importance since it fixes the size and age of the Universe. At a symposium at the Space Telescope Science Institute, experts from around the world presented the latest results from a plethora of techniques for determining the Hubble constant. The value has always been controversial, but at this meeting experts' results agreed for the first time to within about 20%. Based on the meeting, this book presents twenty-three specially written review articles. They provide a comprehensive account of the Hubble-constant debate with the latest results from gravitational lensing, supernovae and novae, the Tully-Fisher relation, the Sunyaev-Zeldovich effect, globular clusters, planetary nebulae, light echoes, and the Hubble Space Telescope Key Project. This timely volume provides a standard reference for graduate students and researchers in astronomy and cosmology.

This volume reviews the current status with respect to both theory and observation of the extragalactic distance scale. A sufficient accuracy is required both for a precise determination of the cosmological parameters and also in order to achieve a better understanding of physical processes in extragalactic systems. The "standard candles", used to set up the extragalactic distance scale, reviewed in this book include cepheid variables, RR Lyrae variables, novae, Type Ia and Type II supernovae as well as globular clusters and planetary nebulae.

In recent years an enormous amount of cosmological data has come from well known projects such as the Hubble Space Telescope (HST) and the Cosmic Background Explorer (COBE). This book explains and makes sense of this vast array of new observational data in terms of its impact on current cosmological models. With new theories and a plethora of data feeding cosmology in the 1990s, Gregory Bothun sets about the task of re- assessing our cosmological models. He outlines exactly what the latest observations are, and how they should be seen as either consistent or in conflict with current cosmogenic scenarios. In this search for a reconciliation of current data with competing theory, he explains how Einstein's idea of a cosmological constant has now become a viable hypothesis. This authoritative text should be valuable to all those studying cosmological observations at advanced undergraduate or beginning graduate level. Bothun draws a path through cosmology by defining a trajectory that is based on the data. This should also provide a framework for professional cosmologists and related readers in physics as it presents a solid observational foundation which either supports or conflicts with present theory. The book is illustrated including many CCD images of galaxies. Given the rapidly changing nature of the field, this book is supported by a World Wide Web site of supplementary material that is designed to readily update the material in the book.

The application of standard measurement is a cornerstone of modern science. In this collection of essays, standardization of procedure, units of measurement and the epistemology of standardization are addressed by specialists from sociology, history and the philosophy of science.

How can the interior of the Sun, white dwarfs and other stars be studied by stellar seismology? What can Doppler imaging tell us about high-degree pulsations? What impact are CCD and infrared observations having on extending the Cepheid and RR Lyrae distance scale? And how are other classes of pulsators providing independent checks of the distance scale? These and many other critical questions are answered in this timely review of the dramatic advances made in pulsating star research in the last decade. This survey collects together more than thirty comprehensive reviews and over one hundred summaries of research papers from the 139th IAU Colloquium, held in Victoria, British Columbia. Together these cover all aspects of recent developments in the field of variable star research and preview some of the exciting advances anticipated for the next decade. This volume provides an essential review for graduate students and researchers.

In a unique collaboration, Nature Publishing Group and Institute of Physics Publishing have published the most extensive and comprehensive reference work in astronomy and astrophysics. This unique resource covers the entire field of astronomy and astrophysics and this online version includes the full text of over 2,750 articles, plus sophisticated search and retrieval functionality and links to the primary literature. The Encyclopaedia's authority is assured by editorial and advisory boards drawn from the world's foremost astronomers and astrophysicists. This first class resource is an essential source of information for undergraduates, graduate students, researchers and seasoned professionals, as well as for committed amateurs, librarians and lay people wishing to consult the definitive astronomy and astrophysics reference work.

Distance determination is an essential technique in astronomy, and is briefly covered in most textbooks on astrophysics and cosmology. It is rarely covered as a coherent topic in its own right. When it is discussed the approach is frequently very dry, splitting the teaching into, for example, stars, galaxies and cosmologies, and as a consequence, books lack depth and are rarely comprehensive. Adopting a unique and engaging approach to the subject An Introduction to distance Measurement in Astronomy will take the reader on a journey from the solar neighbourhood to the edge of the Universe, discussing the range of distance measurements methods on the way. The book will focus on the physical processes discussing properties that underlie each method, rather than just presenting a collection of techniques. As well as providing the most compressive account of distance measurements to date, the book will use the common theme of distance measurement to impart basic concepts relevant to a wide variety of areas in astronomy/astrophysics. The book will provide an updated account of the progress made in a large number of subfields in astrophysics, leading to improved distance estimates particularly focusing on the underlying physics. Additionally it will illustrate the pitfalls in these areas and discuss the impact of the remaining uncertainties in the complete understanding of the Universes at large. As a result the book will not only provide a comprehensive study of distance measurement, but also include many recent advances in astrophysics.