In December of 1972, the Apollo 17 astronauts Eugene Cernan and Harrison Schmitt got to do something awesome: They took a joyride on the moon. A long one. The pair piloted their mission's Lunar Roving Vehicle 19.3 nautical miles (which is also 22.210 statute miles, or 35.744 kilometers) over the moon's dusty, roadless terrain, collecting scientific samples along the way.
Their trip -- Thelma and Louise, with a better car and a happier ending -- was notable not just for the photos it produced or the payloads it collected. The distance Cernan and Schmitt traversed on that foreign soil -- those 20-odd miles of moon-driving -- has marked the longest stretch that any NASA vehicle has ever tread on ground other than Earth.
Until now, that is.
Today, the team that operates Opportunity, NASA's unexpectedly long-lived Mars Exploration Rover, received a transmission from the Red Planet: The rover, moving from one segment of Mars's Endeavor Crater to another, drove 263 feet. Which means that Opportunity's total odometry since it landed on Mars in January 2004 is now ... 22.220 statute miles.