NASA scientists say they have completed mobility tests on California sand dunes in preparation for operating the Curiosity rover currently on its way to Mars. Researchers with the agency\'s Mars Science Laboratory mission took a test rover to Dumont Dunes in the Mojave Desert this week to improve knowledge of the best way to operate Curiosity, which is heading to Mars for an August landing at the Red Planet\'s Gale Crater, NASA reported Friday. The test rover utilized a full-scale version of Curiosity\'s mobility system but was stripped down so it weighs about the same on Earth as Curiosity will weigh in the lesser gravity of Mars, the researchers said. Tests on windward and downwind portions of dunes will help the rover team make decisions about driving Curiosity on dunes near a mountain in the center of Gale Crater, they said. Curiosity is on track for landing Aug. 5 to begin a two-year prime mission to investigate whether the area around its landing site has ever offered an environment favorable for microbial life.