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OAD, the Office of Astronomy for Development, one of the most significant innovations within the IAU, was created at the XXVII General Assembly in Rio de Janeiro in 2009 and opened in 2011. The new office brought together and strengthened several activities of the IAU aimed at helping astronomers in developing or isolated countries to keep in touch with their colleagues elsewhere and up-to-date with the developments in our science. Those activities were mediated through the old commission structure by Commission 38 (Exchange of Astronomers) and Commission 46 (Astronomy Education and Development) which oversaw the International Schools of Young Astronomers (ISYA), the Visiting Lecturer Programme (VLP) and Teaching for Astronomy Development (TAD). In addition, Jorge Sahade, during his term as IAU President (1985–1988), formed the Working Group for the Promotion and Development of Astronomy, as a sub-committee of the Executive Committee, and asked the present writer, then a Vice-President, to act as chair. That Working Group (later renamed the Working Group for the Worldwide Development of Astronomy, WGWWDA) operated within the context of the already existing services of the IAU and in cooperation with the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS). In this paper, the writer gives an account of the activities of the WGWWDA both during and between General Assemblies, until the year 2000, shortly after which he relinquished responsibility for them.
In Manchester, a WG was set up to work on the implementation of the 9th catalogue of orbits of spectroscopic binaries (SB9), superseding the 8th release of Batten et al. (1989) (SB8). SB9 exists in electronic format only. The web site http://sb9.astro.ulb.ac.be was officially released during Summer 2001. This site is directly accessible from the Commission 26 web site, from BDB (in Besancon) and from the CDS (at least).
I. Hubeny Today, the discussion will be open to the general audience. In Sessions C, D, and E, we have talked about models and modelling techniques so I expect the discussion will focus on these topics.
I. Hubeny Welcome to the last panel meeting. We invite general comments either from the audience or from the panelists.
V. Trimble Well, Mercedes started us with a vocabulary item and I think I would like to end with a vocabulary item. When they were first discovered, we called them ‘extra solar system planets’ which was descriptive and fine, but it's just rather cumbersome. At some point they became ‘extra solar planets.’ Now I have never seen a planet inside the Sun. And therefore ‘extrasolar’ is not a good descriptor. ‘Exoplanets’ is OK, but now that there are so many of them that perhaps they are simply ‘the planets.’ When you want to specialize to ours, you could say ‘solar system planets.’ Think how much ink it would save.
M. Richards: Several talks today have expressed fuzzy boundaries to describe the objects called “stars.” Is the following classification correct? Are stars restricted to objects that have masses greater than 0.089 solar masses and begin making energy with hydrogen burning? Do we include the stellar remnants: the white dwarfs and neturon stars? Do we include the brown dwarfs because they burn lithium or deuterium. We know that planets are not in this group since they have no energy production.
I. Hubeny Does anyone from the panel have a theme question to start with today?
V. Trimble It's another one-liner: From an active galaxy meeting many years ago when people talked about spiral structure. I was reminded by Dr. Rucinski's talk of Lodewijk Woltjer's remark: “The larger our ignorance, the stronger the magnetic field.”
The Program Group for World-wide Development of Astronomy (PG-WWDA) is one of nine Commission 46 program groups engaged with various aspects of astronomical education or development of astronomy education and research in the developing world. In the case of PG-WWDA, its goals are to promote astronomy education and research in the developing world through a variety of activities, including visiting astronomers in developing countries and interacting with them by way of giving encouragement and support.
The SB9 Working Group of Commission 30 aims at compiling the 9th Catalogue of Orbits of Spectroscopic Binaries. By definition, this is a never ending task as orbits of newly discovered systems keep appearing in the literature. Despite this, the working group tries to catch up with the delay as nothing was done in between 1989 when the 8th catalogue by Batten et al. and 2000 when the WG was settled. In 2006, at its business meeting, the WG decided to focus on the completeness of systems rather than on completeness of orbits. If the latter is a valuable objective, only the former is useful to any statistical investigation of spectroscopic binaries.
A systematic study is presented of the heteroepitaxial growth of B12As2 on m-plane 15R-SiC. In contrast to previous studies of B12As2 on other substrates, including (100) Si, (110) Si, (111) Si and (0001) 6H-SiC, single crystalline and untwinned B12As2 was achieved on m-plane 15R-SiC. Observations of IBA on m-plane (1100)15R-SiC by synchrotron white beam x-ray topography (SWBXT) and high resolution transmission electron microscopy (HRTEM) confirm the good quality of the films on the 15R-SiC substrates. The growth mechanism of IBA on m-plane 15R-SiC is discussed. This work demonstrates that m-plane 15R-SiC is potentially a good substrate choice to grow high quality B12As2 epilayers.
The Program Group for the World-wide Development of Astronomy (PG-WWDA) is one of nine Commission 46 program groups engaged with various aspects of astronomical education or development of astronomy education and research in the developing world. In the case of PG-WWDA, its goals are to promote astronomy education and research in the developing world through a variety of activities, including visiting astronomers in developing countries and interacting with them by way of giving encouragement and support.
The current content of the database was presented, emphasising the substantial progress accomplished since the IAU XXIV General Assembly in Manchester, 2000. More than 1 200 stellar systems have been added to the 8th Catalogue over the past six years, for a total of 540 papers compiled. A first paper was published to make the community aware of this facility (Pourbaix et al. 2004).
In keeping with its co-sponsorship by members of both the “close” and “wide” binary star communities, IAU Symposium 240 has been jointly dedicated to the honor of Czech astronomer Mirek J. Plavec and the memory of U.S. astronomer Charles E. Worley.
Kues and Batten (2001, p. 30, fig. 6.17–6.20) described several distinctive, minute, low-spired gastropod specimens from the Desmoinesian (Middle Pennsylvanian) Flechado Formation of north-central New Mexico, assigning them questionably to Lunulazona Sadlick and Nielsen, 1963 because of the strongly developed collabral elements similar to those of that genus. These shells, consisting of three or four inflated whorls, are at most 1 mm in height and the later whorls bear conspicuous, sharp, widely spaced collabral ribs that bend strongly across a wide, slightly flattened band interpreted as a peripheral selenizone. While recognizing these specimens as a distinct, unnamed taxon, Kues and Batten (2001) believed that they likely represent juveniles of an as yet unrecognized larger species of gastropod with a different mature morphology.
Developing countries have many claims on their limited resources and astronomy can expect only a small share of a small “pie”. A useful rule of thumb is that a country’s expenditure on astronomy is likely to be of the same order of magnitude as its per capita Gross National Product multiplied by the number of professional astronomers in the country. In the light of this, we consider how governments of developing countries can help their astronomers, how we can help them and how they can help themselves.
During the past triennium some effort has been put into setting up what we hope will be an effective Working Group which currently has the above composition. Membership includes the Presidents of Commissions 38 and 46 ex-officio, so some regular change is built in every three years, as these Presidents change. Thanks are due to R. Kippenhahn, P. Lena, and J. Sahade, members of the original Working Group, who have retired from its active membership. The Chairman retains an extensive mailing list of about some 100 names. All those on that list will continue to receive the WG Newsletter. The present system is to mail one Newsletter annually, in April. At the time of writing, two such mailings have been made since the last General Assembly.
Only five countries in Africa have resident members of the 1AU, and in some there are, quite literally, only one or two. They are isolated (communication with other countries is often difficult), poorly equipped and poorly financed --some have no current journals at all. Most of Africa faces terrible problems, so it is hardly surprising that our colleagues there have their difficulties. Astronomers are useful in developing countries, however, especially as educators, so we can help the whole continent by helping our own colleagues.
It is often assumed that a binary begins to interact when one of its components makes contact with its Roche lobe, thus “switching on” a new evolutionary process. The example of Y Cygni is used to illustrate the view that the whole lifetime of a binary helps to determine whether or not its components will interact. Of particular importance is the interval between the formation of a binary and the arrival of its components on the main sequence, during which probably all binaries are interacting. Barring accidents, the properties of the components when they reach the main sequence will define the whole subsequent history of the system, including whether or not there will be subsequent phases of interaction triggered by contact with the Roche lobe. Like any other mechanical system a binary will tend towards the state of lowest energy consistent with the constraints on it. This it can do by losing mass, equalizing the component masses, or reducing its separation. We therefore expect systems to tend to small masses to mass-ratios of unity, or to coalesce into single stars. In any given system, probably all three tendencies exist, but one dominates. For example, W Ursae Majoris systems may be fusing into single stars. The rotation, chemical composition, and magnetic fields of the component stars may modify the evolution of a binary and be responsible for the variety of interacting systems that we observe. Most interacting pairs are losing mass to the interstellar medium, so a complete study of binary evolution must consider not only the dynamical, but also the chemical, effects of binary systems on the evolution of the Galaxy.