Bill Allen in JPL's Mars Yard :Bill Allen in JPL's Mars Yard. Credit: NASA/JPL-Caltech. Download image › Bill Allen has thrived as the mechanical systems design lead for three Mars rover missions, but he got his start as a teenager sorting letters for the NASA center. Don't tell Bill Allen he can't take risks. Allen was just 17 years old when he first set foot on the grounds of NASA's Jet Propulsion Laboratory to join the mailroom in the summer of 1981. Voyager had recently encountered Saturn, and the Lab was crawling with members of the media. "It was like walking into a football stadium in the middle of the touchdown. It was electric," he says. "This is something that doesn't go on anywhere else in the world, and to be immersed in it with your first footsteps was crazy. That alone was awe-inspiring."