Year: 1986
Type: article
Abstract: The broad interstellar IR extinction features located at 9.7 and 18 microns wavelength are believed to originate from silicate dust grains. Cosmic abundances suggest that the silicate should have a chemical composition similar to that of olivine, (Mg,Fe)2 SiO4. Olivine is a very common terrestrial silicate mineral of crystalline structure. However, crystalline olivine grains do not fit the interstellar features well. Based on spectroscopic data obtained in laboratory studies and astronomical observations it was concluded that the interstellar silicate grains consist of a material with amorphous rather than crystalline structure. The astronomical arguments and the results obtained in our laboratory experiments which support this view are reviewed.
Author: W. Kraetschmer
Institution: Max Planck Institute for Nuclear Physics
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W1646527493