Saving Spirit : Big Pic Gallery

She's a Fighter: NASA's Mars Expedition Rover Spirit landed on the Martian surface on Jan. 4, 2004, three weeks before her sister rover Opportunity touched down. The mission was planned to last three months, but five years later both robots continue to explore Mars. However, Spirit has had the hardest time; she's lost the functionality of one wheel, she's suffering bouts of amnesia and she's currently stuck in a sand trap.

Image: Synthetic image of Spirit on the flank of "Husband Hill" using an actual photograph taken by the rover in 2005 (NASA/JPL-Caltech/Cornell)

Robots Spying On Robots: The High Resolution Imaging Science Experiment (HiRISE) on board NASA's Mars Reconnaissance Orbiter (MRO) captured this birds-eye view of Spirit on June 13, 2009. The large pale circular shape is known as Home Plate, a low plateau inside Gusev Crater.

Image credit: NASA/JPL-Caltech/University of Arizona

The Invisible Hazard: On April 7, Spirit used her navigation camera to image the path ahead as she rolled up a slope near Home Plate. On May 1, rover drivers announced that one of Spirit's wheels had broken through a crusty dark layer of regolith and become embedded in a bright powder next to a location dubbed "Rock Garden." Since becoming stuck in the sand, the area next to Rock Garden has been aptly named "Troy."

Image credit: NASA/JPL-Caltech

That Sinking Feeling: On April 26, Spirit's wheel appeared to be sitting safely atop the problematic sand trap. Unfortunately, attempts to extricate the wheel failed and it began to sink. Although this is bad, NASA scientists have used this opportunity to study the material exposed in the wheel ditch for signs of past water on the Red Planet. "This has been very much like your car breaking down right next to Disney Land," said Mars rover driver Scott Maxwell in a recent Free Spirit update.

Image: A comparison of the rover wheel before and after it became embedded in the powdery regolith (NASA/JPL-Caltech)

Stormy Weather: Still jammed in Troy throughout August, Spirit's panoramic camera (Pancam) captured images of an incoming dust storm. The resulting blockage of sunlight caused a reduction of power in the rover's system, curtailing some operations.

Image: The central portion of the panorama shows the long ditch dug into the regolith by Spirit's jammed wheel before she became immobilized (NASA/JPL-Caltech/Cornell University)

Virtual Reality: NASA scientists have developed a computer simulation of the Mars rover stuck in the sand trap. With the help of this model, it is hoped a safe plan can be executed to get Spirit back on the road.

Image: The embedded rover wheel is simulated, providing an intimate view of the problem Spirit is facing (NASA/JPL-Caltech)