Recent advances in observational and theoretical efforts in understanding the nature of cataclysmic variables had reached such maturity that there existed a strong, shared feeling among the workers in this field that an international colloquium sponsored by the International Astronomical Union would be timely. To be more specific, this was due primarily to the accumulation of the new data from satellite observatories, such as the International Ultraviolet Observatory (IUE) and EXOSAT, as well as ground-based optical and radio telescopes, and the advances in modeling the putative accretion disks and the thermo-nuclear run-away phenomena in the vinicity of the white dwarf stars in cataclysmic variables. A series of workshops on this subject held in North America over the past several years and that held in Europe in 1985 had all contributed to the advances in our knowledge that led to IAU Colloguium No. 93, held in Bamberg from the 16th to 19th of June 1986. In all, 157 astronomers from 27 countries participated in this conference. Judging from the papers presented, both invited and contributed, and from the enthusiasm seen in discussions, the meeting was indeed a success.

Comets are always very impressive phenomena. Their appearances at regular, but mostly irregular, times excite people who see them. Astronomers have the obvious advantage of being able to see more of comets, and to study them. Their enthusiasm is reflected in the 50 papers in this book, written by more than 90 experts. The reviews in this book clearly describe a landmark in the history of cometary studies. Knowledge gathered up to and including Comet Halley are presented in two volumes. The first volume is about general aspects of observing and studying comets, where they originate and how their evolution develops. The second volume goes into the details of what a comet is: the nucleus, the coma, cometary dust, plasmas and magnetic fields. The book ends with a reflection by Fred Whipple about Comets in the Post-Halley Era. The book discusses all aspects of comets and is therefore suitable for use in graduate level courses. All astronomers and geophysicists interested in comets will find very useful and well-presented information in this book.

Are there other planetary systems like ours? Other planets like ours? Is there life elsewhere in the Universe?' So asks Dr. Lew Allen Jr. in the Foreword. In December of 1992, theorists, observers, and instrument builders gathered at the California Institute of Technology to discuss the search for answers to these questions. The International Conference, entitled Planetary Systems: Formation, Evolution, and Detection' and supported through NASA's newly formed TOPS (Toward Other Planetary Systems) program, was the first of a series of conferences uniting researchers across disciplines and political boundaries to share thoughts and information on planetary systems. The conference was sponsored by NASA, hosted by JPL at Caltech, and endorsed by the 1992 International Space Year Association. These proceedings include discussions of topics ranging from stellar, disk, and planetary formation to new ways of searching for other stellar systems containing planets. The authors represent a wide range of nationalities, disciplines, and points of view. The second international conference took place in December of 1993.

The Bosscha Observatory in Lembang, Java, Indonesia, celebrated in 1983 its 60th anniversary. Since its foundation, the physical properties of binary systems have formed a major research topic of this observatory. Until 1970, the study of visual binaries and the determination of orbits received most emphasis. Since then, also the evolution of close binary systems, such as X-ray binaries, Wolf-Rayet binaries and binary pulsars, has been researched with priority in Lembang. It seemed thus appropriate that a Colloquium devoted to the study of binary systems be held in Lembang at the time of the Observatory's anniversary. In the Colloquium, the role of wide double (and multiple) systems received special emphasis - not only because of the long tradition of visual binary research at Lembang; but also because their role in documenting stellar evolution has been largely overlooked in recent decades, and needs to be brought into focus with the information forthcoming from close binaries. The Colloquium covered the physical properties of visual as well as close binary systems, and their generic relations, in the broadest possible sense. It was sponsored by the International Astronomical Union as IAU Colloquium No. 80 ('Double Stars, Physical Properties and Generic Relations'). After the official opening ceremony, the meeting started with a discussion on the future of astronomy in Asia. The scientific sessions began with the 'V. Bappu Memorial Lecture on the Evolution of Binary Systems', presented by Z. Kopal.

If Zdenek Kopal Department of Astronomy University of Manchester Your Magnificences, my Lord Mayor, ladies and gentlemen! It is a great pleasure for me to respond, on behalf of your foreign guests, to your gracious words of welcome; and to thank you for the wonderful reception which you nave extended to us. The city of Bamberg and its Remeis Sternwarte nas indeed been renowned allover the world for a great many years - as the place where your Observatory's first director, Professor Ernst Hartwig (1851-1923) - in addition to his other titles to fame - collaborated (with Gustav Muller of Potsdam) on the construc- tion of the monumental Geschichte und Literatur des Lirhtwechsels der Veranderlichen Sterne, which since 1918 has (together with its sub- sequent continuation) been a veritable vade-mecum of a1l students of variable stars; where the second director, Professor Ernst Zinner (1886-19]~ prepared his valuable Katalog der Verdachtigen Veranderlichen Sterne (192@ which safeguarded many an astronomer (including the present speaker in the days of his innocence) from premature discovery claims; and whose third director, Professor Wolfgang Strohmeier, initiated in 1959 the tradition of the international colloquia of which ours is the latest successor. It is indeed a great pleasure to welcome Professor Strohmeier - now Emeritus - among us; and to congratulate him on the grace with which he is carrying his years.

During the past years, a number of international astronomical conferences were held at the Remeis-Observatory in Bamberg, four of them sponsored by the International Astronomical Union. The first meeting was organized in 1959 and dealt with Variable Stars, the last one was held in 1981 and focussed on 'Binary and Multiple Stars as Tracers of Stellar Evolution'. The present conference was organized to commemorate the 200th anniversary of the birth of Friedrich Wilhelm Bessel, who was born in Minden on July 22, 1784, and died in Konigsberg on March 17, 1846. When the plan for an international conference on astrometric binaries was presented to several colleagues, we received enthusiastic support and decided to pursue the idea. A Scientific Organizing Committee was soon established, consisting of: Z. Kopal Manchester, u.K. S. M. Gong Nanjing, China (Chairman) M. Grewing Tiibingen, F.R.G. V. Abalakin Pulkovo, U.S.S.R. P. v. d. Kamp Amsterdam, Netherlands J. Dommanget Uccle, Belgium M. Kitamura Tokyo, Japan M. G. Fracastoro Torino, Italy J. Rahe Bamberg, F.R.G. W. Fricke Heidelberg, F.R.G. Ya. Yatskiv Kiev, U.S.S.R. E. H. Geyer Bonn, F.R.G. The meeting took place in Bamberg at the Remeis-Observatory, Astronomical Institute of the University Erlangen-Nurnberg, from June l3 to 15, 1984. The following institutions generously supported the meeting: Deutsche Forschungs- gemeinschaft, Bonn; Stadt Bamberg; Universitat Bamberg; Universitat Erlangen- Nurnberg; University of Manchester.

The systematic study of the planets has experienced a slow but steady progress from the efforts of a single individual (Galileo Galilei, 1564-1642) to nations that individually and collectively create whole agencies and complex infrastructures devoted to the exploration and understanding of our solar system. This quest for knowledge continues in earnest today as we attempt to understand Earth's unique place among its closest neighbors. Known diversities emphasize fractionation processes that may have occurred in the nebula during early solar system formation, and the vastly different evolutionary paths taken by the planets and their satellites. The discovery of similarities and differences among the planets has given rise to a discipline of "Comparative Planetology. " Here terrestrial properties and giant planet atmospheres are viewed and probed, surface geologies are related to atmospheres and oceans, interior structures are envisioned, magnetic fields mapped, and bizarre differences in satellites and ring systems continue to enlighten, amaze and confound the detectives of planetary science. A science organizing committee with international participation was formed to develop a conference program to address the basic issues and the fundamental processes that are common among the planets. The goals of the meeting were twofold: first the production of a reference source on comparative planetology for academia, and second, the provision of an impetus for NASA to begin a program devoted to this emerging science discipline. The conference program accommodated seventeen invited papers and nineteen poster presentations.

The idea of having a conference in Padova describing the results obtained by the Galileo spacecraft and the characteristics of the Telescopio Nazionale Galileo began in 1995, when a number of colleagues from both sides of the Atlantic began exchanging suggestions and ideas. Looking at the schedules of the two teams, it was clear that the beginning of January 1997 would be a good time to hold the conference; these dates also luckily coincided with the dates of the memorable discovery of the Medicean moons of Jupiter by Galileo Galilei in Padova in 1610. To emphasize these three elements, the name of the conference was then proposed and accepted by the involved parties: NASA and JPL in the United States, the German space agency DARA, the University of Padova, and the Astronomical Observatory in Padova. I wish to recall a few key dates: In January 1610, Galileo--from his house in Padova--had the first hint of three and then four stars connected to Jupiter. In December 1995, the probe released from the spacecraft entered the atmosphere of Jupiter, and the spacecraft entered orbit about Jupiter. These extraordinary events were followed at JPL by a number of representatives of many institutions and space agencies. In June 1996, the Telescopio Nazionale Galileo was inaugurated by the King of Spain Juan Carlos I, in the presence of Prof. Luigi Berlinguer, Minister of University and Science. These ceremonies occurred as the spacecraft started touring the moon Europa.

The systematic study of the planets has experienced a slow but steady progress from the efforts of a single individual (Galileo Galilei, 1564-1642) to nations that individually and collectively create whole agencies and complex infrastructures devoted to the exploration and understanding of our solar system. This quest for knowledge continues in earnest today as we attempt to understand Earth's unique place among its closest neighbors. Known diversities emphasize fractionation processes that may have occurred in the nebula during early solar system formation, and the vastly different evolutionary paths taken by the planets and their satellites. The discovery of similarities and differences among the planets has given rise to a discipline of "Comparative Planetology. " Here terrestrial properties and giant planet atmospheres are viewed and probed, surface geologies are related to atmospheres and oceans, interior structures are envisioned, magnetic fields mapped, and bizarre differences in satellites and ring systems continue to enlighten, amaze and confound the detectives of planetary science. A science organizing committee with international participation was formed to develop a conference program to address the basic issues and the fundamental processes that are common among the planets. The goals of the meeting were twofold: first the production of a reference source on comparative planetology for academia, and second, the provision of an impetus for NASA to begin a program devoted to this emerging science discipline. The conference program accommodated seventeen invited papers and nineteen poster presentations.

Comets are always very impressive phenomena. Their appearances at regular, but mostly irregular, times excite people who see them. Astronomers have the obvious advantage of being able to see more of comets, and to study them. Their enthusiasm is reflected in the 50 papers in this book, written by more than 90 experts. The reviews in this book clearly describe a landmark in the history of cometary studies. Knowledge gathered up to and including Comet Halley are presented in two volumes. The first volume is about general aspects of observing and studying comets, where they originate and how their evolution develops. The second volume goes into the details of what a comet is: the nucleus, the coma, cometary dust, plasmas and magnetic fields. The book ends with a reflection by Fred Whipple about Comets in the Post-Halley Era. The book discusses all aspects of comets and is therefore suitable for use in graduate level courses. All astronomers and geophysicists interested in comets will find very useful and well-presented information in this book.

Recent advances in observational and theoretical efforts in understanding the nature of cataclysmic variables had reached such maturity that there existed a strong, shared feeling among the workers in this field that an international colloquium sponsored by the International Astronomical Union would be timely. To be more specific, this was due primarily to the accumulation of the new data from satellite observatories, such as the International Ultraviolet Observatory (IUE) and EXOSAT, as well as ground-based optical and radio telescopes, and the advances in modeling the putative accretion disks and the thermo-nuclear run-away phenomena in the vinicity of the white dwarf stars in cataclysmic variables. A series of workshops on this subject held in North America over the past several years and that held in Europe in 1985 had all contributed to the advances in our knowledge that led to IAU Colloguium No. 93, held in Bamberg from the 16th to 19th of June 1986. In all, 157 astronomers from 27 countries participated in this conference. Judging from the papers presented, both invited and contributed, and from the enthusiasm seen in discussions, the meeting was indeed a success.