Mars Curiosity

Engineers work on a model of the Mars rover Curiosity at the Spacecraft Assembly Facility at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., Thursday, Aug. 2, 2012. After traveling 8 1/2 months and 352 million miles, Curiosity will attempt a landing on Mars the night of Aug. 5, 2012. (AP Photo/Damian Dovarganes)