The devotion of an IA U symposium entirely to the topic of chromo spheric fine structure at a time when models of the spherically symmetric chromosphere are still evolving constitutes a valid recognition of the growing feeling among solar astron- omers that the chromosphere cannot be understood independently of its discrete structural features. Network structure, which seemingly borders the photospheric supergranule cells, persists intact throughout the chromosphere and most of the chromosphere-corona transition region. The network is the locus of the bright coarse mottles, and the spicule...

The proposal to organize a Symposium on circumstellar matter and extended atmo- spheres in binary systems was first made by the Dominion Astrophysical Observatory to the Executive Committee of the International Astronomical Union in the summer of 1969. It received the support of the presidents of Commissions 29 (Stellar Spectra), 30 (Radial Velocities), 36 (Stellar Atmospheres), and 42 (Photometric Double Stars). Approval in principle was given by the Executive Committee almost immediately, and the Committee further suggested that the Symposium be officially designated the Struve Memorial...

Proceedings of IAU Symposium No. 53 held in Boulder, Colorado, 21-26 August 1972

be hoped. We have improved measurements by at best a factor of 3. So thIS paper, unfortunately, IS really a status report rather than a progress report. There are, however, a few new results to mention. I shall present the results wIthout glVlng any detaIls of the experImental apparatus. In general, sources of error and problems in these measurements are not determined by the apparatus itself. The most important new result IS that of Paul Henry (1971), who employed a radiometer mounted on a rotatmg platform suspended beneath a balloon. Because he employed a rotatmg platform he was able to...

The IAU Symposium No. 62, 'The Stability of the Solar System and of Small Stellar Systems' was held in Warsaw in Poland during the Extraordinary General Assembly of the IAU in commemoration of the SOOth anniversary of the birth of Nicolaus Copernicus. The Symposium was sponsored by Commission 7 (Celestial Mechanics) and cosponsored by Commissions 4 (Ephemerides) and 37 (Star Clusters and Asso- ciations) of the IAU and by IUTAM. The Organizing Committee included Y. Kozai (Chairman), J. A. Agekjan, A. Deprit, G. N. Duboshin, S. Glska (Local represen- tative), M. Henon, B. Morando and C. Parkes...

Proceedings of IAU Symposium No. 58 held in Canberra, Australia, August 12-15, 1973

lAD Symposium No. 66 was held in Warsaw from September 10th to September 12th 1973, in connection with the Extraordinary General Assembly of the lAD. It was arranged by lAD Symposium No. 35 and the Scientific Organising Committee con sisted of A. G. Massevitch (Chairman), A. V. Tutukov (Secretary), H. M. van Horn, N. Dallaporta, J. P. Ostriker, B. Paczynski, G. Ruben, E. Schatzman, R. J. Tayler and A. Weigert. This volume contains the full texts of all of the invited papers presented at the Symposium, apart from that delivered by R. P. Kraft, which is published in abstract because it is...

This Symposium was held at Surfer's Paradise, Queensland, Australia, from 7 to 11 September 1973. The Organizing Committee, chaired by J. P. Wild, consisted of A. Boischot, A. Bruzek, J. T. Jefferies, G. Newkirk, T. Takakura, and V. V. Zhelez nyakov. We are indebted to the Local Organizing Commettee, chaired by S. F. Smerd and including R. G. Giovanelli, R. E. Loughhead, N. G. Seddon, K. V. Sheridan, and J. P. Wild, for advice in preparing this volume as well as for the smooth arrangement of the sessions. In addition, the session chairmen and reporters are to be thanked for their assistance...

Colloquia and symposia have almost become a tradition among the variable-star astronomers; those held more or less regularly at Bamberg and Budapest have become well known. For a change, this time the organizing committee of Commission 27 decided to hold an LA. U. symposium in Moscow and to adopt as a special topic the relation between variable stars and the evolution of stars and stellar systems. This symposium, No. 67 in the LA. U. series, was prepared by two committees, a by B. V. Kukarkin, and a local one with V. A. Ambartsumian scientific one chaired as chairman, and G. S. Khromov as...

The idea of holding this Symposium has its origin in a conversation with G. Con to- poulos during the winter of 1973. It was then clear that the progress realized in Stellar Dynamics since the Thessaloniki symposium had given a new shape to the field. Other meetings such as the C. N. R. S. colloquium held in Paris in 1967 or the LA. V. colloquium held in Cambridge, England, in 1970 had in the meantime given opportunities to review the advances achieved in several branches of this field. We thought that time had come to organize a general confrontation of the new results obtained in the...