The vehicle will have a width of 1.3m and a length of 3m. While being small enough to fit into the space provided in the interplanetary spacecraft, his size will allow two astronauts to sit side-by-side in their surface suits and have enough length to accomodate the Radioisotope Thermoelectric Generators (discussed in Power section), other types of research and survival equipment, and emergency supplies.

A high grade (700 series) aluminum and zinc alloy will be employed for the frame of the surface vehicle. After tempering and anodizing, this alloy should provide a desirable mix of durability, light weight, and strength. Other benefits of using aluminum are the ease with which it can be machined and its relatively low cost. Other options that were discussed, but ultimately rejected, included titanium alloys (too expensive and not sufficiently better than the aluminum to justify the increased cost) and carbon fiber. Although carbon fiber is both strong and light, it is very expensive and not sufficiently abrasion-resistant to withstand long stays on the Martian surface. 
 
 

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