Meet "Curiosity," NASA's new nuclear-powered Mars roverS

This fall, Nasa will launch its latest Mars rover dubbed "Curiosity" to further the Red Planet exploration done by Spirit and Opportunity. The differences? This one is the size of a compact car, shoots lasers and runs on nuclear power.

Curiosity, which is expected to land on Mars in 2012, has been engineered to travel 200 meters a day, with the capability to roll over obstacles as high as 25 inches. It's energy source — the radioactive decay of plutonium 238 — will give it at least a full Martian year, or 687 Earth days, of power and heat. Among its instruments: a spectrometer to measure minerals kicked up by a blast from a built-in laser.

Because spacecar.