IAU S258 discusses the problem of estimating ages of stars and stellar populations, a difficult challenge in astrophysics.

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.

A complete record of the formal organisational and administrative proceedings of the XXVII General Assembly of the International Astronomical Union.

Astronomy in Focus presents the most relevant contributions from the Focus Meetings included during the XXX IAU General Assembly held in Vienna, Austria, from 20-31 August 2018. Focus meetings are proposed by groups of scientists with aims to promote cross-disciplinary interactions while maintaining a well-defined focus on a particular topic. They usually address a new scientific area or an emerging field that is not well, or in some cases not at all, represented under the IAU's existing Commission structure. The XXX IAU General Assembly included six scientific symposia, a special symposium focused on the IAU's centenary and fifteen Focus Meetings. The latter comprised twelve scientific Focus Meetings plus two on the mission and activities of the IAU Offices of Astronomy Outreach and Astronomy for Development and the final one promoted by the Working Group on Global Coordination of Ground and Space Astrophysics.

The versatile and available GNSS signals can detect the Earth’s surface environments as a new, highly precise, continuous, all-weather and near-real-time remote sensing tool. This book presents the theory and methods of GNSS remote sensing as well as its applications in the atmosphere, oceans, land and hydrology. Ground-based atmospheric sensing, space-borne atmospheric sensing, reflectometry, ocean remote sensing, hydrology sensing as well as cryosphere sensing with the GNSS will be discussed per chapter in the book.

This book considers the history of modern astronomy and astrophysics in Japan by comparing with the development of astrophysics in western countries. Astrophysics essentially arose in three separate fields: astronomical spectroscopy, stellar structure, and survey of celestial objects. This book introduces readers to the state of astronomy back to the Tokugawa era (18th – 19th centuries), when the chief task of astronomers was limited to the calendar making. With the so-called Meiji revolution (1868), the situation drastically changed. The Meiji Government promoted the modernization of Japan by hiring numbers of foreign instructors in political, social, and cultural affairs, including Construction of Observatory and University. Then the foreign studies of Japanese researchers lasted for many years. After the Second World War, Japan experienced great social and economical growth allowing the constructions of large optical, radio, and space instruments. With this background astrophysics progressed and eventually flourished. The book ends by highlighting Japanese contributions to international collaboration up to the early 21st century. Readers of this book will understand how astrophysics has grown into one of the major sciences in Japan, and how the works of individual astronomers are contributing to the global advancement of knowledge of the universe.