The new $2.5 billion rover is designed to analyze samples of Mars rock for signs that our planetary neighbor is, or ever was, habitable to life. Weighing in at 1 ton, Curiosity is too heavy to land with the assistance of cushioning airbags, like NASA's previous two Mars rovers, Spirit and Opportunity.
Instead, parachutes will slow the MSL descent stage toward Mars at first. Then, the descent stage will use rocket engines to dampen its speed further. Finally, at about 115 feet (35 meters) above the surface, the Sky Crane system will lower Curiosity, wheels-down, toward the ground, attached to nylon tethers. The rover is designed to be gently settled on the surface, after which the Sky Crane will detach and fly off to land a distance away. [How Curiosity's Nail-Biting Landing Works (Pictures)]
The plan requires a large number of sophisticated parts to work impeccably, and is utterly different than any previous mechanism used to land a machine on another planet, prompting some to charge that it's a scheme Rube Goldberg would have approved.
"A lot of people seem skeptical of it. I'm not," said Stephen Gorevan, chairman of New York City robotics firm Honeybee Robotics, which built Curiosity's internal Sample Manipulation System, but wasn't involved with the landing strategy. "I just think, the thing has been so tested. I see the electromechanical elements, I'm an engineer, I see at least each individual element of the scheme seems very reliable to me. It's new, it's daring, but I see it working."