IMPLICATIONS OF DIELECTRIC PROPERTIES OF THE MARTIAN SURFACE SOIL ON THE SEARCH FOR SUBSURFACE LIQUID WATER OR ICE RESERVOIRS

摘要

The main goal of the MARSIS experiment on board Mars Express is the search for liquid water and ice on the surface and subsurface of Mars, which is thought to be essential in the search for extraterrestrial life. The reflection and attenuation of the MARSIS radar waves at the surface or at subsurface layers depend strongly on the dielectric properties of the Martian soil. Therefore the exact mineralogical composition of the Martian surface material is an important factor. Especially ferric oxides, such as hematite and maghemite, are expected to contain appreciable portions of nanoscaled phases. These extraordinary small grains may have contributions to the dielectric constant completely different from the 50 μm ones. Therefore we propose laboratory measurements with Martian analogues in the space simulation facility.