This book shows that astronomical discovery is a complex and ongoing process comprising various stages of research, interpretation and understanding.

"This is to our knowledge, the first work collecting the designations of various types of astronomical objects from single stars to galaxies, to X-ray sources, to the Egg Nebula, MonoGem or Vel X, Y, Z." -- Introduction.

The XXth General Assembly of the International Astronomical Union was held in Baltimore, Maryland USA from August 02 to 11, 1988. The Inaugural Ceremony on August 02 was held in the presence of representatives of the United States Governn:ent, t~e S~ate of Maryland, the City of Baltimore and the host institution -the Johns Hopkins Umverslty- as well as of the National and Local Organising Committees. The scientific programme maintained the high standards of the Union and the scientific proceedings may be found either in this volume or in volume 8 of Highlights of Astronomy. The scientific programme was organised by the 40 Commission Presidents and coordinated by the General Secretary (1985-1988), Dr. J.-P. Swings. The local arrangements were effectively made through the National Organising Committee under the Chairmanship of Prof. F. Drake and the Local Organising Committee under the co-Chairmanship of Prof. A. Oavidsen and Dr. R. Giacconi. The smooth day to day operation of the meeting resulted from the incomparable dedication of Karen Weinstock and Harold Screen.

The International Astronomical Union (IAU) was founded in 1919, in the wake of the First World War, together with its sister Unions in related natural sciences. It will thus turn 100 years in 2019. Written by a mixed team of insiders and outsiders, this book presents the IAU in the changing context of the historical, scientific and technological development of astronomy during the past 100 years. While much important scientific progress took place already before 1945, the book naturally focuses on the accelerating evolution during the second half of the century. In the past few decades, the previously narrow IAU focus on organising professional astronomy has broadened to include societally relevant activities such as addressing the hazard of asteroid impacts, the planetary status of Pluto in the Solar System, and the hugely successful International Year of Astronomy. Most recently, it is spearheading a combination of science literacy and public outreach. The book will be of interest to professional astronomers as well as an astronomically interested general audience. The book features live personal interviews with as many of the key actors as still possible.

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.

Advances in Machine Learning and Data Mining for Astronomy documents numerous successful collaborations among computer scientists, statisticians, and astronomers who illustrate the application of state-of-the-art machine learning and data mining techniques in astronomy. Due to the massive amount and complexity of data in most scientific disciplines