IAU Symposium 135 on Interstellar Dust was hosted and co-sponsored by NASA's Ames Research Center from July 26-30, 1988. The symposium was held at the lovely campus of Santa Clara University situated around the historic Santa Clara Mission in California. The meeting was made possible by generous grants from the Astron­ omy and Relativity Branch of the National Aeronautics and Space Administration and the Galactic Astronomy Program of the National Science Foundation. The International Astronomical Union provided travel grants to a few participants from countries with limited travel funds. We are particularly grateful for the support and services rendered by the dedicated staff at NASA's Ames Research Center and to the" SET! Institute for professionally and expeditiously administering the U.S. grants. This symposium brought together 199 scientists representing 19 different coun­ tries. The wide range of interest and expertise of the participants - all in some way related to interstellar dust - is reflected in the great variety of topics that were discussed during the symposium ranging from UV, visible and IR observations of interstellar extinction to quantum-statistical calculations of the IR emission from highly vibrationally excited molecules. During the course of the meeting, 41 invited review papers and 140 contributed papers were presented. This book is a collection of the invited review papers. The contributed papers have been published in a companion volume, NASA CP-3036, available from National Technical Information Service, Springfield, Virginia 22161, USA.

Inhalt

Section I: Dust in the Diffuse Interstellar Medium.- Measurements of Interstellar Extinction.- Insights on Dust Grain Formation and Destruction Provided by Gas-Phase Element Abundances.- Interstellar Extinction in External Galaxies.- Dust towards the Galactic Centre.- Linear and Circular Polarization in the Diffuse ISM.- Diffuse Interstellar Bands.- Visible/UV Scattering by Interstellar Dust.- Section II: The Overidentified Infrared Emission Features.- Infrared Emission from Reflection Nebulæ.- Observations of HII Regions and Planetary Nebulæ: the Infrared Emission Bands.- Aromatic Infrared Emission in Cirrus Clouds.- The Infrared Emission Features and PAHs.- The Infrared Emission Features and HAC Particles.- Optical Properties of Carbonaceous Materials.- Physical and Chemical Properties of PAHs.- The PAH Hypothesis and the Extinction Curve.- A Critical Assessment of the PAH Hypothesis.- Chemical, Optical and Infrared Properties of QCCs.- Grains, or Molecules? Thermal, or non-Thermal?.- Infrared Emission Mechanism in Large Isolated Molecules.- Panel Discussion on Treatments of Processes in PAH Molecules.- Ection III: Dust in Dense Clouds.- The Heating of Interstellar Gas by Dust.- Dust in Dense Clouds.- Dust and the Gas Phase Composition of Dense Clouds.- Polarized Infrared Emission from Dust.- Section IV: Dust in Galaxies.- Far Infrared Emission from Galactic and Extragalactic Dust.- Observations of Infrared Emission from Galaxies.- Section V: Optical Properties of Grains.- On the Interpretation of the ? 2175 Å Feature.- Pitfalls in Calculating Scattering by Small Particles.- Fractal Dust Grains.- Section VI: Interstellar Dust Models.- The Core-Mantle Model of Interstellar Grains and the Cosmic Dust Connection.- Bare Carbon/Silicate Theories.- Grains in Diffuse Clouds: Carbon-Coated Silicate Cores.- Open Panel Discussion on Interstellar Grain Models.- Section VII: Interstellar Dust and the Solar System.- Interstellar Molecules in Meteorites.- Interstellar Grains in Meteorites: Diamond and Silicon Carbide.- Interstellar Dust in Collected Interplanetary Dust Particles.- Comet Dust: Connections with Interstellar Dust.- Section VIII: Bust Formation and Destruction.- Dust Destruction in the Interstellar Medium.- Sources of Stardust in the Galaxy.- The Composition of Dust in Stellar Ejecta.- Dust Condensation in Stellar Outflows.- Infrared Emission from Dust in Supernovae and Supernova Remnants.- Summary.- Critical Questions for the Future.- Contributed Papers.- Addresses of Participants.- Object Index.- Index of Molecules.