Sand on Mars is a whole different question.
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With millions of years of accumulated dust and dirt taking a chance with the tires they chose , hoping to have a firm surface with excellent traction is not a plan and was not wise ...
I didn’t say their design was wise.
But sand is not dust, and no accumulation of dust has been found on Mars either. Dust mingled with sand creates Road Base, which they obviously have not found in the valley.
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