The XXth meeting of the IAU in Australia in 1973 made the venue for the IAU Symposium No. 59 on Stellar Instability and Evolution, at Mount Stromlo Obser vatory on August 16-18, a very appropriate one. Many of the current and former staff of Mount Stromlo Observatory (operated by the Australian National Univer sity) have specialized in the study of variable stars and it was with considerable pleasure that Mount Stromlo Observatory accepted the responsibility of hosting and making the local arrangements for IAU Symposium No. 59. The Scientific Organizing Committee was particularly active in formulating the program and comprised Drs N. Baker, P. Demarque, M. Feast, G. Herbig, I. Iben, P. Ledoux, J. Ostriker and E. Schatzman. The aim of the Committee was to integrate the review and contributed papers on the particular instability mechanisms involved, their observational manifestations and their relation to the internal structure of the star as inferred from its evolutionary history. The Local Organizing Committee consisted of Miss P. Petrie and A. W. Rodgers.

Proceedings of IAU Symposium No. 59, held at Mount Stromlo, Canberra, Australia, August 16-18, 1973

Inhalt
I / Survey of the Problems in Radial Stellar Instability and its Relation to Stellar Evolution.- The Theoretical Situation.- The Observational Evidence.- II / Pulsation and the Young Disc Population.- Recent Progress in Linear and Non-Linear Calculations of Radial Stellar Pulsation.- Population I Cepheids Theory and Observation.- The Temperature Scale for Classical Cepheids.- uvby Colours of Cepheid Variables.- K. Bahner and L. N. Mavridis / Period Variations in Galactic Cepheids (Title only).- Non-Pulsating Stars and the Population I and II Instability Strips.- Pulsation Modes and Period-Luminosity-Color Relations for the Short-Period ? Scuti Stars.- The Abundances and Gravities of the ? Scuti, AI Velorum and RR Lyrae Stars.- The Dwarf Cepheids.- Multiple Periodicities in ö Scuti Stars.- ? Canis Majoris Stars in the (?, [C1]) Plane.- A Search for ? Cephei Pulsation in Extreme Composition Models.- III / Large Mass Stars, Stability in Supergiants, Critical Masses.- Non-Linear Instability of Stars with M> 100 M?.- On the Variabihty of Supergiants of types B-G.- Recent Studies of the Brightest Stars in the Magellanic Clouds.- Variations in the Line Spectrum of A-Type Supergiants.- IV / Halo and Old Disc Populations.- A. Red Variables and Evolution on the Giant Branches.- Red Variables of the Old Disc and Halo Populations.- Dynamical Models of Asymptotic-Giant-Branch Stars.- B. Short Period Variables, Horizontal and Asymptotic Branch Evolution and Planetary Nuclei.- Variable Stars and Evolution in Globular Clusters.- The Characteristics of the Field RR Lyrae Stars in the Magellanic Clouds.- On Some Pecuhar Features in the Sequences of the Old Open Star Clusters.- Models for Nuclei of Planetary Nebulae and Ultraviolet Stars.- V / Eruptive and Explosive Variables.- Explosive and Eruptive Stars.- On the Binary Nature of the Slow Nova, RR Telescopii.- Non-Radial Pulsations of Dwarf Novae.- Tests of the Binary Hypothesis of Novae through Nova Nebulae Observations.- Proposed Search for Fast Variables.- VI / Instability Mechanisms.- A. Non-Radial Pulsations Magnetic Fields.- Non-Radial Oscillations.- The Sun as a Pulsating Rotating Star.- Instabilities of Magnetic Fields in Stars.- Magnetic Fields in X-Ray Binary Systems.- The Oscillations and the Stability of Rotating Masses with Magnetic Fields.- B. Rotation Close Binaries.- Rotational Instabilities and Stellar Evolution.- Perturbation of the Non-Radial Oscillations of a Gaseous Star by an Axial Rotation, a Tidal Action or a Magnetic Field.- Mass-Ratio Determination in Contact Binaries.- Index of Names.