It wasn't a fast drive, nor particularly long, but it will be remembered in the history books as one of humanity's greatest off-road adventures. After traversing almost 5 miles of Martian terrain, NASA's Spirit rover has fallen silent, and the agency thinks the vehicle has reached the end of its journey.
From the NASA announcement:
Spirit last communicated on March 22, 2010, as Martian winter approached and the rover's solar-energy supply declined. The rover operated for more than six years after landing in January 2004 for what was planned as a three-month mission. NASA checked frequently in recent months for possible reawakening of Spirit as solar energy available to the rover increased during Martian spring. A series of additional re-contact attempts ended today, designed for various possible combinations of recoverable conditions.
"Our job was to wear these rovers out exploring, to leave no unutilized capability on the surface of Mars, and for Spirit, we have done that," said Mars Exploration Rover Project Manager John Callas of NASA's Jet Propulsion Laboratory, Pasadena, Calif.
Spirit drove 4.8 miles (7.73 kilometers), more than 12 times the goal set for the mission. The drives crossed a plain to reach a distant range of hills that appeared as mere bumps on the horizon from the landing site; climbed slopes up to 30 degrees as Spirit became the first robot to summit a hill on another planet; and covered more than half a mile (nearly a kilometer) after Spirit's right-front wheel became immobile in 2006. The rover returned more than 124,000 images. It ground the surfaces off 15 rock targets and scoured 92 targets with a brush to prepare the targets for inspection with spectrometers and a microscopic imager.
Here is one of the final images Spirit beamed back to Earth:
On the brighter side, the Opportunity rover is still rolling, and is now en route to a Martian crater 3 miles ahead.
PHOTOS: Top, Rendering of a NASA Mars rover. Below, One of the last images from Spirit, both via NASA.
Hat Tip: BoingBoing