NASA scientists are envisioning its most ambitious mission yet, a journey that will haul its largest payload of scientific instruments.
Then, as a laboratory on wheels, the rover Curiosity will explore the Red Planet for signs of past life, secrets buried in the Martian terrain.
"From that we will be able to determine whether or not the ancient environment that once existed on Mars was suitable for microorganisms that might have been living on the surface," said John Grotzinger, a scientist on the project.
Among many challenges: a wheel system that will enable the rover to rove. Earlier explorers were the size of golf carts. Curiosity is closer to a small SUV. It is atomic-powered to work for 23 months.
Its weight makes for a trickier voyage and landing.
"It takes about nine months to make it to Mars, and we approach Mars at a little over 12,000 miles an hour," said Adam Steltzner, chief engineer of entry, descent and landing.
And it must slow down to 1 mile per hour. To slam on the brakes, parachutes will open and rockets must activate. Moments from impact, the rover is released.
"It is going to hang below the jetpack and the pair of them are going to touch down on the surface of Mars a little bit over 1 mile an hour," said Steltzner.
Scientists will aim for a zone that appears shaped by ancient flooding. There, the rover will bore in to determine mineral content. Or with a laser beam, zap a rock farther away. The vapor will reflect different kinds of light according to what that material it is.
At JPL, engineers work in a sterile lab, fine-tuning for a November launch.
The project's cost is $2.5 billion. Scientists break that down to what the average American will pay.
"What this is worth to you as an individual is about the cost of a latte," said Grotzinger.
And scientists hope it will yield more knowledge about how life begins and ends.