Właściwości fizyczne regolitu Marsa na tle badań modelowych

Abstract

PHYSICAL PROPERTIES OF MARTIAN REGOLITH IN THE LIGHT OF MODEL STUDIES Summary The paper presents a review of the published data on basic physical properties and estimates of petrological composition of Martian regolith. Of the regolith models proposed so far those obtained by the striking method of basalt disintegration after heat treatment in atmosphere (by crashing with 5 mm copper bullet shooted out of the hydrogen galloper with speed of 5,8 km•s-1) appear most consistent with telemetric data. Comparison of the models proposed so far makes it possible to state that the surface of Mars is covered with fine-grained regolith. The regolith is a product of chemical rocks. Mixing of regolith is good even at depth of several meters and the material appears similar to that from the surface. Packing density of condensed regolith from the depth of several meters in estimated at 1.7 Mg•m-3 (at the average), and porosity - at about 40%. Packing density of loose regolith from the surface of Mars drops to about 1.2 Mg•m-3 and porosity increases to about 60%. Moreover, thin layers of fine-dispersion eolic materials (with grain size below 200 μm) are expected at the very surface. lf packing density of these materials is lower than 0.9 Mg•m- 3, their porosity should be around 70%.