Mr. Ladislav Mrgavec, from the office of the President of the Czech Republic, Mr. Miloš Gregar, from the Lord Major's department, Professor Václav Pačes, President of the Academy of Sciences, national representatives, our hosts, IAU members and invited participants:

Following the Inaugural Ceremony, the President welcomed the participants to the first plenary working session of the IAU XXVII General Assembly, notably the representatives of the National Members.

The members of the Resolutions Committee 2003-2006 were Christopher J. Corbally (chair, USA), Jocely S. Bell Burnell (UK), Matthew Colless (Australia) Georges Meylan (Switzerland), Silvia Torres-Peimbert (Mexico), Rachel L. Webster (Australia), and Robert Williams (USA).

This chapter presents the reports of Business Meeting of IAU Divisions, Commissions, Working Groups and Program Groups, held during the IAU XXVI General Assembly in Prague, 14-25 August 2006. The reports have been written by the out-going presidents and chairpersons.

Division I provides a focus for astronomers studying a wide range of problems related to fundamental physical phenomena such as time, the inertial reference frame, positions and proper motions of celestial objects, and precise dynamical computation of the motions of bodies in stellar or planetary systems in the Universe.

The IAU Division I Working Group on Nomenclature for Fundamental Astronomy (NFA) was established by the IAU XXV General Assembly with the task of providing proposals for new nomenclature associated with the implementation of the IAU XXIV GA resolutions (2000) and to make related educational efforts for bringing the issue to the notice of scientists in the community.

This business meeting was held from 16:00 to 17:30. Toshio Fukushima and George Kaplan were welcomed as the next president and vice-president, respectively. The following, in no particular order, are the summary reports from the various offices. The full versions will be made available on the Commission 4 website at <http://iau-comm4.jpl.nasa.gov/>.

In his address to the Commission, the outgoing president A. Milani explained what he considers have been done well in the past triennium, what has been done only in part, and what has not been done at all. Among the things in which the performance was rated good, he mentioned the successful sponsorship and/or co-sponsorship of four meetings (IAU Colloquia 196 and 197, and Symposia 229 and 236) which have been held in the previous period, as well as of the Symposium on exoplanets to be held next year in China. The only failure in this respect was the proposed meeting in India, which failed already at the proposal definition stage. Also, Milani expressed his satisfaction with the triennial report which has been compiled for the occasion, and his gratitude to the collaborating authors.

The Business Meeting was opened by the president, Imants Platais. He presented the agenda which was unanimously approved. This session was attended by 40 participants. The meeting approved Dafydd Evans as secretary of minutes.

Various experiments have definitely demonstrated that one-micron accuracy (0.″06) on the definition of stellar images on CdC plates cannot be claimed, as it was speculated back in 1999. More realistically, a 2-3 micron accuracy is achievable, getting worse toward the survey magnitude limit, with an average magnitude error of 0.3. The level of astrometric accuracy corresponds to a 0.″2 - 0.″3 error in position at Epoch 1900, which, once used as first Epoch for proper motion determination in combination with modern epoch observations, can produce errors at the level of 2-5 mas/yr, thereby allowing to detect stellar motions larger than 0.″01/yr, which at a distance of 500 pc from the Sun correspond to ~25-60 km/s tangential velocity. Therefore, the AC/CdC heritage collection can be regarded as a highly valuable first-epoch material, e.g., for the realization of a Tycho-2 extension to fainter magnitudes (~15 photographic), especially in selected areas where radial velocity data are available, for the exploration of stellar kinematics beyond our solar neighborhood.

Most of the Commission's three 90-minute time slots at the General Assembly were devoted to a series of 20 and 50 minute presentations, informally termed “Time and Astronomy”. The first part of the meeting was dedicated to time and general relativity. The second part of the session was dedicated to pulsar timing.

Division II provides a forum for astronomers studying a wide range of problems related to the structure, radiation and activity of the Sun, and its interaction with the Earth and the rest of the solar system.

The IAU Division II WG on International Collaboration in Space Weather has as its main goal to help coordinate the many activities related to space weather at an international level. The WG currently includes the international activities of the International Heliospheric Year (IHY), the International Living with a Star (ILWS) program, the CAWSES (Climate and Weather of the Sun-Earth System) Working Group on Sources of Geomagnetic Activity, and Space Weather Studies in China. The coordination of IHY activities within the IAU is led by Division II under this working group. The focus of this half-day meeting was on the activities of the IHY program. About 20 people were in attendance. The Chair of the WG, David F. Webb, gave a brief introduction noting that the meeting would have two parts: first, a session on IHY activities emphasizing IHY Regional coordination and, second, a general discussion of the other programs of the WG involving international Space Weather activities.

Division III gathers astronomers engaged in the study of a comprehensive range of phenomena in the solar system and its bodies, from the major planets via comets to meteorites and interplanetary dust.

After a brief discussion it was agreed that this membership is well distributed in terms of geography, gender, and fields of planetary work.

The meeting was attended by six from the WG (K. Aksnes, J. Blunck, G. Consolmagno, B. Marsden, R. Schulz, V. Shevchenko) and two from the Task Groups (D. Morrison, J. Watanabe). Also the incoming WG members E. Bowell and R. Courtin, as well as some guests, attended.

This report of the business meeting at the 2006 IAU GA is based on notes provided by Edward Tedesco, past president, and on the minutes taken by Petrus Jenniskens, secretary of Commission 15 in the triennium 2003 to 2006, with additional notes from the current secretary of Commission 15, Daniel Boice. For political reasons the incoming President, Walter Huebner, was unable to attend the General Assembly.

The meeting of the Physical Properties of the Minor Planets Working Group of IAU Commission 15 took place on 24 August, and was devoted to purely scientific matters, since other topics (organization of the Minor Planet WG, need of a new web page, election of the new chairman) had been already discussed during the business meeting of Commission 15, on 22 August. A brief summary of the talks given during the meeting is given in what follows.