Influence of organic molecules on ice properties on solar system bodies

Physical properties of ice depend on structural parameters, globally described as the texture of the material. These parameters are the porosity, the grain size, the material strength and the local density, just to mention a few. We performed laboratory experiments to investigate the influence of organic molecules (aliphatic hydrocarbons) on the thermal conductivity of ice and dust mixtures, as they might occur on comets or the surface of icy satellites like Europa. An evaluation of the experiments showed that a certain amount of organic constituents might act as a kind of glue that enhances the material strength and also the thermal conductivity. Thus, the history of such icy bodies is also influenced by the amount of available organic components in the material. (Author)