Ken Edgett, principal investigator, MAHLI Camera, Mars Exploration Program, discusses what we’ve learned from Curiosity and the other Mars rovers during a “Mars Up Close” panel discussion, Tuesday, August 5, 2014, at the National Geographic Society headquarters in Washington. Photo Credit: (NASA/Bill Ingalls)

Ken Edgett, principal investigator, MAHLI Camera, Mars Exploration Program, discusses what we’ve learned from Curiosity and the other Mars rovers during a “Mars Up Close” panel discussion, Tuesday, August 5, 2014, at the National Geographic Society headquarters in Washington. Photo Credit: (NASA/Bill Ingalls)

Ken Edgett, deputy principal investigator for NASA Mars Descent Imager, holds a ruler used as a depth-of-field test target. The instrument took this image inside the Malin Space Science Systems clean room in San Diego, CA, during calibration testing.