Since landing on Mars to begin its planned 90-day mission on January 3, 2004, the Spirit rover has provided NASA with unprecedented information on the geology and atmosphere of the Red Planet. But scientists say its days may be numbered.
Map of trapped rover
Although it's still operational, Spirit has become stuck in deep sand, rendering it immobile. Spirit has been trapped at this location on the west side of a crater known as "home plate" for the past nine months. On Wednesday, NASA scientists said they're running out of maneuvers for getting Spirit's wheel unstuck.
Hung up on Mars
In this image taken June 2, 2009, we can see how Spirit has become immobile, with its wheel stuck in a fine soil. Using the microscopic camera mounted on the soil sampler arm, Spirit took this panoramic image of the situation currently challenging its operators back on Earth.
"The highest priority for this mission right now is to stay mobile, if that's possible," said Steve Squyres of Cornell University and principal investigator for the rover project.
Tracks on Mars
If scientists cannot free Spirit soon, they will give up and instead try to improve its tilt. Collecting more sunlight would give the solar-powered rover more time and energy with which to attempt to escape the sand trap. And, NASA says, it would at least keep the onboard instruments powered so it can collect data from its current location.
But time is not on Spirit's side. It's trapped in the southern hemisphere of Mars, where it is currently autumn and the amount of sunshine reaching it is steadily declining. Unless the tilt can be improved or winds clear off some of the dust that has collected on the solar panels, Spirit could run out of the power it needs to make more escape attempts, or "extraction activities," as early as January. By May, Spirit might not have enough power to remain in operation.
Here, Spirit turns its camera backward to view its own tracks.
Trapped on Mars
The view from the Spirit rover looking north, back along its path, from the point where it got trapped last April. The rover is believed to be straddling the rim of a hidden crater. Note the front-left wheel, nearly buried in powdery soil.
This area was named "Rub al Khali" after a similarly desolate area in Saudi Arabia.
Drilling into rock
The 0.35-inch hole drilled into this rock, called Clovis, is the deepest one driven into a Martian rock.
Since losing the use of its right-front wheel in 2006, Spirit has been forced to move backward. Looking back after moving 22.7 meters on the 1,861st Martian day (on March 28, 2009), we can see the bright soil churned up by dragging the immobile wheel.