Determination of Mars soil mechanical properties will improve future lander mission success and provide narrower constraints for geomorphological modeling. A soil mechanics investigation was conducted wherein soil mechanical properties were determined by computer reconstruction of mass wasting features observed in photographs of Mars Exploration Rover landing sites and analysis of natural slope stability. Mars soil mechanical properties were compared with thermal inertia measurements and a correlation is presented. Tests with rovers and equipment for Mars surface exploration and various past laboratory experiments have incorporated a number of different Mars soil simulants. Standard laboratory measurements were conducted to characterize the shear strength, grain size distribution, and densities of various Mars soil simulants. From these measurements, the ability of a given simulant to appropriately represent the mechanical properties of in situ Mars soils was judged. Specific simulants are recommended for certain regions of Mars.

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Adverse effects of dust accumulation on spacecraft and rover surfaces hinder the functioning of equipment on Mars and consequently limit mission duration. Hence, dust is an important parameter in the design, development, and testing of equipment for Mars surface missions. A review of Martian dust composition, transport, deposition, adhesion, and removal is presented. Martian dust has consistent average chemical and mineralogical composition over the entire planet. Sources of dust transport and deposition on the surface of Mars include ordinary atmospheric settling, dust storms, dust devils, near surface saltation, and artificial human/robotic disturbance of the regolith. Mechanisms of dust adhesion include chemical bonding, cementation, ice bridges, capillary forces, van der Waals forces, and electrostatic forces. There are a number of different methods to cause particle removal including vibration, centrifuge, impact, electrostatic repulsion, liquid or air flow, thermophoresis, and direct manipulation using a mechanical device. This paper presents a summary of what is known about Martian dust and its removal to date.

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