Hydrous Alteration of Amorphous Silicate Smokes: First Results

Results of the initial studies of the hydrous alteration of amorphous Mg-SiO smokes indicate that although these materials readily adsorb water, the silicate structure is much more stable at 360/sup 0/K than expected. We have observed drastic changes in the relative absorption strengths of the 10- and 20-micron ''silicate'' features that appear quite rapidly at 750/sup 0/K; these observations might have important implications for the interpretation of cometary dust spectra. Observations of the development of 3.4-3.5 micron features possibly due to hydrocarbons in the spectra of processed Mg-SiO smokes have raised the exciting possibility that these amorphous condensates could act as Fischer-Tropsch type catalysts to produce hydrocarbons in the primitive solar nebula.

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