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But first, Curiosity has to survive its landing. Much larger than earlier Mars rovers Spirit and Opportunity -- the 1-ton machine is roughly the size of a very small car -- Curiosity posed a significant challenge to the engineers tasked with getting it down through the Martian atmosphere and onto the soil of the Red Planet.
Not to quibble, but the Lunar Excursion Module (LEM) for the Apollo missions to the moon weighed over 5 tons. Although there was no atmosphere through which to penetrate and the gravity was less, the LEM did have to return into orbit.
I don't know much about the Reynolds' numbers for the Martian atmosphere, but I found the design a bit over-complicated. One would think a glider for the final phase, completing a flare out and stall on the landing would have been easier to do than the rocket powered "sky hook," but I have little doubt that such a system was considered and and rejected in favor of this one.
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The science instruments carried by Curiosity will be looking for, among other things, carbon compounds and signs of whether Mars is, or ever might have been, habitable. The rover's uphill climb will take it through eons of Mars' geological evolution.
"The really cool thing about the Gale stratigraphic succession to me is it's a tour through nearly the entire history of Mars, where we can begin to understand these major changes in the environmental history of the planet," project scientist John Grotzinger said in an interview with CNET.