Bøger i International Astronomical Uni serien

IAU Transactions XXIIB summarizes the work of the XXIInd General Assembly. The discourses given during the Inaugural and Closing Ceremonies are reproduced in Chapters I and III, respectively. The proceedings of the two sessions of the General Assembly will be found in Chapter II, which includes the Resolutions and the report of the Finance Committee. The Statutes, Bye-Laws and a few working rules of the Union are published in Chapter IV. The Accounts and other aspects of the administration of the Union are recorded in Chapter V, together with the report of the Executive Committee for this last triennium, and provide the permanent record for the Union in the period 1991-1994. This volume also contains the Commission reports from The Hague compiled by the Presidents of the Commissions (Chapter VI). Finally, Chapter VII contains the list of countries adhering to the Union and the alphabetical, geographical and commission membership lists of about 8000 individual members. The IAU still appears to be unique among the scientific Unions in maintaining this category of individual membership which contributes in a crucial way to the spirit and the aims of the Union.

Ken Freeman I would like to pick out a few items that I found particularly interesting. The choice probably reflects my ignorance, because many of these topics are no doubt more known to most of you. I am fairly sure that some of them are basic and important. We will start with the first session. There were three closely related papers on the evolution of massive stars, the formation of open clusters and associations and the IMF. We learned that clusters appear to form in initially bound clouds 6 of masses between 10'+_10 M , but star formation is a destructive process. Most of the gas is@ lost and the remaining stars then find themselves in an unbound system, which naturally disperses on a dynamical time. As a result of this, star formation is typically a fairly inefficient process, at least on the scale of open clusters. However (as Heggie pointed out) it seems to be somewhat more efficient on smaller scales, as evidenced by the fairly high incidence of binary stars. To form a bound cluster requires a higher efficiency of star formation, typically 30% or more, and we see how the three papers of this morning session relate: the initial mass function and the timing of where and when the DB stars form dictate the likely fate of the system.

I.A.U. Symposium No. 133, "Mapping the Sky: Past Heritage and Future Directions" was held at Paris on 1-5 June, 1987. The rationale for this meeting is to combine historical and modern aspects of mapping the sky; historical in that the meeting celebrates the initiation of the carte du Ciel at the Observatoire de Paris in 1887 and evaluates its impact on astrometry and astronomy in general. And modern in the sense that now in optical, radio and other wavelengths the sky is and needs to be charted in detail. The Symposium also commemorates the 150th anniversary of the first trigonometric parallax. The proposal for the meeting closely involved the sponsoring I.A.U. Commissions 24 and 41 and their respective officers. The Scientific Organizing Committee included the two current presidents of these commissions as co-chairmen (A.R. Upgren and J.A. Eddy, respectively) along with V. Abalakin. S. Debarbat, Ch. de Vegt, R.L. Duncombe, H.K. Eichhorn, M. Hoskin, J.A. Hughes, C. Jaschek, P.G. Kulikovsky, C.A. Murray and P.A. Wayman. The L.O.C. consisted of P. Charvin (chairman), S. Grillot, L. Garin and R. Weinstein; they were helped by M. Alibert (secretary), G. Rault, S. Seguier, J. Counil and S. Debarbat. Additional financial support was provided by the Division of History of Science, International Union for the History and Philosophy of Science.

The driving idea, in organizing this Symposium on "Relativity in Celestial Mechanics . and Astrometry" was that, in recent years, the ac­ curacy of several Astrometric techniques has so much increased that re­ lativistic effects are no more marginally mentioned in academic presen­ tations but have become an intrinsic part of the interpretation of all the positional data. Techniques such as V. L. B. I. , space probes, lunar lasers, etc . . . have greatly contributed to reduce the accuracy level to an angular equivalent of a few milliarc-seconds. HIPPARCOS will extend this trend to stellar astrometry and new proposals aim at gaining ano­ ther one or two orders of magnitude in observing precision. In paral­ lel, great progress has also been made in the theories of motion of ce­ lestial bodies and more rigourous treatments within the frame of general relativity become necessary. The definition of reference frames and of various coordinate times become also a major problem in the intercompa­ rison of observations produced by different methods. This Symposium gave to people using relativistic corrections in reducing their measurements or in constructing various theories of mo­ tion a chance to exchange their experience in the field and to confront it with theoreticians in general relativity. The Symposium was approved by the IAU in 1983 and it was organi­ zed by the Institute of Theoretical Astronomy of the USSR Academy of Sciences on May 28-31, 1985.

PROCEEDINGS IAU S)1WOSIUM 112 Michael D. Papagiannis Department of Astronomy Boston University Boston, Massachusetts 02215, USA 1. THE SYMPOSIUM AND THE PROCEEDINGS IAU Symposium 112 - The Search for Extraterrestrial Life: Recent Developments, was held in Boston and in particular at the new Science Center of Boston University, June 18-21, 1984, and was attended by about 150 participants from 18 different countries. It was the first official scientific meeting organized by IAti Commission 51, the youngest of all IAU Commissions, which was established only in 1982 at the 18-th IAU General Assembly at Patras, Greece. This Volume of the Proceedings contains nearly 70 papers with about 90 authors from 20 different countries, including two papers from our Soviet colleagues (Kardashev and Slysh) who had not been able to attend our Symposium in Boston. The Volume is divided into eight Sections, the first of which serves as a general introduction, and the other seven correspond to the seven Sessions of the Symposium.

In June 1983 the Astronomical Institute of the State University of Groningen, founded by Kapteyn about 100 years ago, celebrated its one-hundredth anniversary. At the suggestion of its Chairman, R.J. Allen, the Kapteyn Institute invited the International Astronomical Union to mark the centenary by holding a Symposium on "The Milky Way Galaxy". The purpose of the Symposium was to review recent progress in the study of our Galaxy, to define current problems, and to explore prospects for future development. The Symposium programme would emphasize the large-scale characteristics of our Galaxy, and highlight both the historical development of our understanding of the Milky Way Galaxy and the importance of studies of external galaxies to this understanding. The Symposium was sponsored by four IAU Commissions: 33 (Structure and Dynamics of the Galactic System), 28 (Galaxies), 34 (Interstellar Matter) and 41 (History of Astronomy). The Scientific Organizing Committee, listed on page xviii, represented a broad range of nationalities and of expertise, including two historians of science. A meeting of the Committee, held during the IAU General Assembly at Patras, provided an excellent opportunity to discuss plan and format of the Symposium, topics and speakers; thereafter, the-Committee was regularly consulted by letter and telephone. IAU Symposium 106 was held at Groningen on 30 May - 3 June 1983, in the new building occupied by the Kapteyn Institute since January 1983. There were about 200 participants, coming from as many as 25 countries.

IAU Symposium 101, Supernova Remnants and Their X-ray Emission, was held on the Island of San Giorgio, Venice, 30 August - 2 September 1982. It was co-sponsored by the National Research Council, Italy, the University of Padua, the Observatory of Padua, and the International Astronomical Union, and was hosted by the Cini Foundation. The contents of this volume show the wide range of disciplines that are involved in supernova remnant research. Many new results were presented, not only from the X-ray observations from the Einstein Observatory but also from observations at optical and radio wavelengths. This has led to the stimulation of theoretical work, much of which attempts to accommodate in a more unified way all of these observations. Research on supernova remnants of all ages was reported. Perhaps the most impressive part of all this work is the way in which observations at all wavelengths have extended well outside the Galaxy to other members of the Local Group and beyond. The Symposium was attended by scientists from 15 countries. Twenty­ five invited papers and sixty-eight shorter contributions were presented during the 4-day meeting. Thirty-three of these shorter contributions were presented in poster sessions. This volume contains almost all (89) of those contributions. They are followed by discussions which took place after each verbal presentation. Since the availability of the discussions was left to the individual contributors, they are not complete, but those contained in this volume convey some idea of the nature of the exchanges.

IAU Symposium 103 was held at University College London, August 9-13 1982. This volume contains the proceedings of the meetin- invited papers, abstracts of contributed papers, and discussion. As is nON custanary with the proceedings of IAU Symposia, the manuscript was canpiled fran camera-ready copy. The Editor was responsible for the preparation of the abstracts of the contributed papers and the discussion, the authors of the invited papers for the preparation of their 0Nn reviews. The discussion at the meeting was lively and infonnative, and the Editor hopes that a reasonably faithful and readable record of the discussion is to be found in these proceedings. In accordance with the wish of the Scientific Organising Committee, an object index has been canpiled and appended. It is to be hoped that the index will augment the usefulness of the volune. The Editor is greatly indebted to M. J. Barlow for his help in preparing the index. Financial assistance for the meeting was provided by the IAU and University College London. The hospitality received during the excursion to the Old Royal Observatory and National Maritime MUseum, Greenwich, is gratefully acknowledged. The task of editing these proceedings has been greatly facilitated by the excellent secretarial assistance of V. A. Kerr. David Flower Durham, October 1982 xiii D. R. Flower (ed.), Planetary Nebulae, xiii.

The idea of the symposium came during the XVllth General Assembly of the IAU at Montreal. The Working Group on Be stars adopted both the proposal of holding a meeting, and of having it at the Universitats­ sternwarte Munich. The meeting was organized under the auspices of IAU Comm. 29 (Stel­ lar Spectra) and the sponsorship of Comm. 45 (Stellar Classification). The Scientific Organizing Committee was composed of Mercedes Jaschek (chairman), W. Bonsack, C. de Loore, A. Feinstein, H. G. Groth, P. Harmanec, L. Houziaux, A. M. Hubert-De1p1ace, L. S. Luud, A. Slettebak and A. Underhill. The members of this committee are to be thanked for their devotion to the organization of what turned out to be a very successful meeting. The program was organized on an observational approach, comprising sessions on photometry, polarization, spectroscopy, infrared observations, rotation and binarity, X-ray observations, UV observations and mass loss, and atmospheric models. Each session started with an invited summary paper, followed by a number of contributions. The different sessions were chaired by A. Feinstein, R. Sta1io, C. de Loore, Ch. Fehrenbach, J. P. Swings, C. Jaschek, A. Sapar, G. T. Traving, M. de Groot and H. G. Groth. Upon request of the Working Group., a special session was devoted to bibliographic problems and observing campaigns. The Dean of the Faculty for Physics 0.£ the Ludwig-Maximilians-, Universitat welcomed the participants at the beginning of the Symposium. The meeting was closed by a summary talk, delivered by ~. P. Snow.

IAU Symposium 97, Extragalactic Radio Sources, was held at Albuquerque, New Mexico August 3-7, 1981. It was co-sponsored by IAU Commissions 28, 40, 47 and 48 and by URSI Commission J. Financial and organizational support were provided by the National Radio Astronomy Observatory, the University of New Mexico, and the National Science Foundation. A wide variety of interesting objects and phenomena can be covered under the heading "Extragalactic Radio Sources", and a diverse set of topics was in fact discussed at the symposium. Radio galaxies, quasars, Seyfert galaxies and BL Lacertids received the most attention, but normal galaxies, the galactic center, and even SS433 were also discussed. While the unifying theme of the symposium was radio emission, studies at all wavelengths--X-ray, UV, optical, IR, and radio--were included. In general, the emphasis was on individual objects and the physical processes associated with them, but there were also papers on statistical studies and cosmology. The symposium was attended by 209 scientists from 18 countries.

This volume presents the Proceedings of International Astronomical Union Symposium No.93 on Fundamental Problems in the Theory of Stellar Evolution. It contains the texts of all the invited papers, the abstracts of the contributed papers that were read by one of the attending author(s), and edited discussions. Only one abstract is included in this volume from each author who attended, and the abstracts of papers which were read on behalf of absent author(s) are not included. Those papers, which were read but are not included in the volume, are indicated by asterisks in the table of contents. The meeting took place at the University Hall, Kyoto University, Kyoto, Japan from July 22 to 25, 1980, and was sponsored by IAU Commission 35 on Stellar Constitution and co-sponsored by the IAU Commission 42 on Close Binary Stars. Locally, the Symposium was hosted by the Research Institute for Fundamental Physics, Kyoto University with encouragement from the Astronomical Society of Japan. Financial support for the meeting was provided by the IAU, the Japan Society for the Promotion of Sciences, the Japan World Exposition Commemorative Fund, and the Yamada Science Foundation. Preparation for the Symposium and editing of the Proceedings were supported in part by Scientific Research Fund of Japanese Ministry of Education, Science and Culture (530603).

Informal discussions in 1977 among a number of scientists asso­ ciated with solar and interplanetary physics revealed a need for a dialogue between the two often-divergent groups. It was clear that the latter group was dependent essentially on the sun for its raison d'etre. On the other hand it was also clear that the former group could benefit in its search for insight vis-a-vis solar activity by looking beyond the shell of the inner corona. Needless to add that the combined solar/interplanetary topic is relevant to astrophysics when one considers stellar winds and binary star flows. It was felt, there­ fore, that a symposium was essential to bring together, for the first time, leading solar and interplanetary physicists from the interna­ tional community to discuss and record herein their own research. The fundamental physical processes underlying our own capricious star's activity can be understood only by the coupling of solar and interplan­ etary topics in an intimate observational and theoretical structure. This book, intended for active research scientists and advanced grad­ uate students, is an important step in this direction. The background of solar and interplanetary dynamics is provided in Part I (The Life History of Coronal Structures and Fields) and Part II (Coronal and Interplanetary Responses to Long Time Scale Phenomena).

The organization of this Symposium had its beginnings at the International Astronomical Union General Assembly in Grenoble in 1976. The initial "rounding up" of the Scienti­ fic Organizing Committee was begun by Drs. Snow and Swings; most of us who became the eventual organizing committee met a few times during the Assembly and formulated the essential outlines of the meeting. Extensive correspondence with all the committee subsequently established the program. The idea was to bring together both observers and theoreticians to discuss the stellar winds and mass loss rates and their effects on evolutions of O-type stars. On the observational side, there are now spectroscopic data from the far UV to the near IR regions concerning the stellar winds. There is also information about the free-free emission in the wind from the IR and radio portions of the spectrum. Fortunately, these different detection methods give more or less the same mass loss rate for the one star, s Pup" which has been observed at all wavelengths. One of the intents of the first three sessions of this Symposium is to outline the eXisting data on mass loss rates as it per­ tains to the O-type stars.

IAU Symposium No. 82, "Time and the Earth's Rotation", met to discuss modern research in the field of the rotation of the Earth with particu­ lar emphasis on the role of new observational techniques in this work. The use of these techniques has prompted a new look at the definitions of the traditional reference systems and the concepts of the rotation of the Earth around its center of mass. Specific topics discussed were time, polar motion, reference systems, conventional radio interferometry, very'long baseline interferometry (VLBI), Doppler satellite methods, satellite laser ranging, lunar laser ranging, and geophysical research concerning the Earth's rotation. Improvement in the accuracy of the observations is a key to possible solutions of the many unsolved problems remaining in this field. It appears that such improvement, using both classical and new techniques, is forthcoming in the near future. This will surely contribute to a better understanding of some of the long-standing questions concerning the rotation of the Earth around its center of mass and lead to an improved knowledge of the rotating, deformable Earth. This volume contains the papers presented at IAU Symposium No. 82 as well as the discussions provoked by these papers. It is hoped that it captures the principal points of the meeting and that it will contribute not only to a better understanding of existing problems, but also to future research in time and the Earth's rotation.

We have in this volume, compiled a connected account of the proceedings of the Symposium on Wolf-Rayet and High-Temperature Stars held at Buenos Aires. The Organizing Committee had assigned broad areas of topical interest to be reviewed by invited speakers. Each of these presentations was followed by lengthy discussions that were tape recorded and transcribed later. These discussions have been edited only to a limited extent. We have shortened them and rearranged them to bring about a greater coherence. We have, however, attempted to retain the tenor of the discussions, the flavour of impromptu remarks and the continuity of an argument. Much of the success of such a venture depends on the contributors to the discussions. To be able to make these thoughts available to a larger audience has been the task of those re­ sponsible for the elaborate tape recording of the proceedings. We thank those at the Instituto de Astronomia y Fisica del Espacio for the efficient way in which this re­ sponsibility has been discharged. Many at Buenos Aires and Kodaikanal have contrib­ uted efficient assistance to the preparation of this volume and we are deeply indebted for their help. In particular, two amongst these, Nora Martinez and A. M. Batcha have contributed overwhelmingly both to the organization of the symposium and the final preparation of the symposium volume. Financial support for this symposium came from the International Astronomical Union and the Argentine National Research Council.

The changing character of the IAU General Assemblies becomes most clear from a comparison of the agenda of the Brighton meeting with that of one of the earlier meetings. The fourth General Assembly (Cambridge Mass. , 1932) had about 240 participants, registered guests included, the Brighton meeting had about 2300 people attending. The Cambridge meeting lasted 5, working days, of which, however, three half days were exclusively devoted to excursions, leaving four real meeting days. At that time the nearly 30 commissions had each only one meeting, during part of a morning or afternoon; some commissions did not meet at all. There was one public lecture, by Sir Arthur Eddington, on 'The Expanding Universe'. Most of the small European countries were represented by two or three delegates only, but the delegations of France and Great Britain were composed of 20 and 18 scientists respectively; at that time there were only two delegates from Germany. After the Brighton General Assembly, with about 200 commission meetings - one commission met eleven times! - six Joint Discussions, four Invited Discourses, a Special Meeting and hardly time for excursions, there were a few complaints about too many overlapping meetings.

The IAU Symposium No. 47 The Moon was held in the School of Physics of the University of Newcastle-upon-Tyne, England, from 22 to 26 March 1971. The Meet­ ing was sponsored by Commission 17 and co-sponsored by URSI. The Symposium was supported financially by the IAU. The Scientific Organizing Committee included Prof. S. K. Runcorn, Chairman (University of Newcastle-upon-Tyne), Prof. H. Alfven (Royal Institute of Technology, Stockholm), Prof. G. Colombo (University of Padova), Prof. A. Dollfus (Observatoire de Paris), Prof. T. Gold (Cornell University), Dr K. Koziel (Jagellonian University, Poland), Prof. G. P. Kuiper (University of Arizona), Dr B. J. Levin (U. S. S. R. Academy of Sciences), Dr A. A. Mikhailov (U. S. S. R. Academy of Sciences), Prof. A. E. Ringwood (Australian National Univer­ sity) and Prof. H. C. U rey (University of California). The Local Organizing Committee included Prof. S. K. Runcorn (Chairman), Dr G. Fielder, Prof. W. R. Hindmarsh, Prof. Z. Kopal and Prof. W. H. McCrea. This book includes the majority of papers presented at this the second IAU Sym­ posium on The Moon: comparison with the previous IAU Symposium on The Moon held in Leningrad, a decade earlier, makes clear the great advances made possible in our knowledge of the Moon and solar system by space technology. Academician A. A.

Two years ago, just before the Prague meeting of the International Astronomical Union, Armin Deutsch made the bold suggestion that the space spectroscopists hold a joint symposium with the ground-based observers. At that time the rocket observa­ tions of stellar spectra seemed too meagre to make such a meeting worthwhile, but we proceeded in the hope that there would be significant new results available by 1969. IAU Commissions 29 and 44, on Stellar Spectra and Observations from Outside the Terrestrial Atmosphere respectively, agreed to sponsor the symposium so that the organization was given to the Joint Working Group of these commissions. Conse­ quently, the Organizing Committee, which met first in Prague, consisted of A. Deutsch, M. W. Feast, L. Houziaux, V. G. Kurt, N. G. Roman, J. Sahade, A. B. Underhill, and R. Wilson, with myself as Chairman. Later COSP AR was invited to join in spon­ soring the symposium and T. Chubb was added as their representative. We were specially pleased when C. de Jager invited us to the Netherlands and offered the services of the Utrecht Observatory for the local organization. He suggested we hold the meeting at the new Lunteren Conference Centre located in a wooded area some 35 km east of Utrecht. The modern facilities of the Centre and the hospi­ tality of its staff contributed much to the enjoyment of our four days there.