Astrochemistry : From Molecular Clouds to Planetary Systems pages:435-443
IAU Symposium 197 location:Sogwipo, South Korea date:23-27 Aug. 1999
ISO has opened new infrared windows for spectroscopy, enabling detailed studies of the composition of the dust particles present in circumstellar disks. For oxygen-rich dust, and in particular for silicates, a forest of new features has been discovered, and comparison with laboratory data has enabled the identification of most of them. Of special relevance is the detection of crystalline silicates, which present themselves as a new diagnostic for studying the formation of comets and planetesimals in the disks surrounding young and, surprisingly, also evolved stars.