The references cited in this section are mostly papers on original laboratory research; compilations and data bases are covered in another section. The references, ordered by atomic number and spectrum, are given in parentheses following the spectral notations. References including experimental data on line structure, hyperfine structure (HFS) or isotope structure (IS) are also included.

The activities of the Commission have continued to focus on controlling unwanted light and radio emissions at observatory sites, monitoring of conditions at observatory sites, and education and outreach. Commission members have been active in securing new legislation in several locations to further the protection of observatory sites.

The Commission supports and coordinates scientific investigations in the Earth rotation and related reference frames. Several changes had been introduced to the structure of Commission 19 since the IAU XXVI General Assembly in Prague, 2006. The Organizing Committee of Commission 19 has been substantially reduced. It consists now of six ex-officio members, the Commission president, vice-president, past president and representatives from the International Association of Geodesy (IAG), International Earth Rotation and Reference Systems Service (IERS), International VLBI Service for Geodesy and Astrometry (IVS), and five members at-large who are nominated by the OC, selected by the Commission members and elected by the IAU GA for a maximum of two terms. The modified terms of reference of Commission 19, the list of members and other details can be found at the Commission website <iau-comm19.cbk.waw.pl/>.

Division X provides a common theme for astronomers using radio techniques to study a vast range of phenomena in the Universe, from exploring the Earth's ionosphere or making radar measurements in the Solar System, via mapping the distribution of gas and molecules in our own Galaxy and in other galaxies, to study the vast explosive processes in radio galaxies and QSOs and the faint afterglow of the Big Bang itself.

The International Heliophysical Year (IHY) is an international program of scientific research and collaboration to understand the external drivers of the space environment and climate. Its activities were centered on the year 2008, the 50th anniversary of the International Geophysical Year. The IHY involves utilizing the existing assets from space and ground as a distributed Great Observatory and the deployment of new instrumentation, new observations from the ground and in space, and public and student education. The IHY officially was launched in February 2007 with an opening ceremony and workshop in Vienna. Many IHY activities, both scientific and educational, have occurred since then. In practice, these activities have taken place over the last several years, and the programs that have been established through the IHY will continue into the future as ‘legacies’ of the IHY.

This report gives an update of developments (since the last General Assembly at Prague) in the areas that are of relevance to the commission. In addition to numerous papers, a new monograph entitled Stellar Spectral Classification with Richard Gray and Chris Corbally as leading authors will be published by Princeton University Press as part of their Princeton Series in Astrophysics in April 2009. This book is an up-to-date and encyclopedic review of stellar spectral classification across the H-R diagram, including the traditional MK system in the blue-violet, recent extensions into the ultraviolet and infrared, the newly defined L-type and T-type spectral classes, as well as spectral classification of carbon stars, S-type stars, white dwarfs, novae, supernovae and Wolf-Rayet stars.

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.

The main purpose of Commission 14 is to foster interactions between the astronomical community and those conducting research on atoms, molecules and solid state particles. One way the Commission accomplishes this goal is through triennial compilations on recent relevant research in atomic, molecular and solid state physics, as well as related chemical fields. The most recent compilations appear in the following set of WG Triennial Reports, which were produced by members of the Working Groups and the Organizing Committee of Commission 14. Before presenting the Reports, we highlight the meetings supported by the Commission.

Commission 41 of the International Astronomical Union deals with all aspects of astronomical history and heritage from ancient sky knowledge to developments in modern astronomy that have occurred within living memory. It encourages and supports research in the history of astronomy and related fields such as archaeoastronomy and is also concerned with the identification, documentation and preservation of vital aspects of our astronomical heritage such as sites, artifacts, instruments and archives. Commission 41 is one of the largest Commissions in the Union, and is a member of Division XII on Union-Wide Activities.

Division XII consists of Commissions that formerly were organized under the Executive Committee, that concern astronomers across a wide range of scientific sub-disciplines and provide interactions with scientists in a wider community, including governmental organizations, outside the IAU.

Commission 46 continues its task in the triennium, which started in September 2006. It seeks to further contribute to the development and improvement of astronomical education at all levels all over the world through various projects initiated, maintained and to be developed by the Commission, and by disseminating information concerning astronomy education.

Division VI provides a focus for astronomers studying a wide range of problems related to the physical and chemical properties of interstellar matter in the Milky Way and other galaxies.

The main goal of the Working Group was to gather astrometric observations made during the triennum as well as old observations not yet published in the data base. The WG encouraged the making of new observations. A Spring School was organized in China in order to teach the observational techniques of natural satellites to students and young astronomers. New theoretical models of the motion of the satellites and fit of the current models to new observations were used in order to make ephemerides of all the planetary satellites with tools useful for observations such as configurations. These ephemerides named MULTISAT are available at <www.imcce.fr/sat> or at <lnfm1.sai.msu.ru/neb/nss/nssephme.htm>.

Astronomers are well aware of the changing nature, volume, and complexity of astronomical data. Most of us are aware that next generation instruments, with Terabyte databases, are going to present enormous challenges to the way that we process data, and our current ways of managing astronomical databases will probably no longer work. So there are a number of initiatives within the astronomical community, most notably the Virtual Observatory, which aim to address these. However, many astronomers are not aware that similar challenges are being met in other disciplines (e.g., geosciences, life sciences, etc.) and that similar solutions are being sought. As a result, astronomy has much to gain from cross-fertilisation with other disciplines.

From Director Dan Green's report, following this report, it is obvious that the Central Bureau for Astronomical Telegrams (CBAT) continues its excellent work. The Electronic Telegrams (CBETs), established in the previous triennium, have become the regular means for fast communication, with the Circulars providing the official and archival record of discoveries and designations. It is regretted that subscriptions to the printed Circulars continue to decline, but inevitable in this age of electronic communication.

The Working Group Stellar Radial Velocity Bibliography is a very small one that was created with the purpose of continuing the cataloging of bibliography of radial velocity of stars made by Mme Barbier in successive catalogues until her retirement in 1990.

Annual reports of the IAU Commission 46 Program Group Teaching for Astronomy Development (TAD) for the years 2006 and 2007 have been published in IAU Information Bulletin 100, 47; and 101, 40. Here the 2008 report is presented.

This triennium began with an action to re-create the Terms of Reference for the Working Group Global VLBI (WG-GV). These had been lost over the years since the Group was established in 1990. Fortunately, the personal archive of one long-term member yielded a copy of the original memorandum by R. D. Ekers, which was found to coincide quite well with current practice and areas of interest. New Terms of Reference, based on modern conditions, were drafted and accepted by both IAU and URSI.

The Commission 46 Program Group Exchange of Astronomers (PG-EA) provides travel grants to astronomers and advanced students for research or study trips of at least three months duration. Highest priority is given to applicants from developing countries whose visits will benefit them, their institution and country, and the institution visited. This program, if used strategically, has the potential to support other Commission 46 programs such as Teaching for Astronomical Development (PG-TAD) and World Wide Development of Astronomy (PG-WWDA). Complete information about the program, and the application procedure, can be found at <physics.open.ac.uk/IAU46/travel.html>.

The Commission 15 report was prepared primarily by the chairpersons of the two working groups: T. Yamamoto of the Comet Working Group and R. A. Gil-Hutton of the Minor Planet Working Group. In particular, the Comet section was produced by T. Yamamoto with the assistance of D. Bockelée-Morvan, H. Kawakita, and D. Prialnik, while the Minor Planet section was produced by R. A. Gil-Hutton with the assistance of A. Cellino, A. W. Harris (DLR), R. Jedicke, A.-C. Levasseur-Regourd, R. M. Schulz, T. B. Spahr, and P. Vernazza. W. F. Huebner was responsible for the Introduction. The final editing and merging of the various sections and subsections of the report was carried out by the Commission Secretary, D. C. Boice.