NASA’s Mars Exploration Rover team made a valiant effort to extricate the Spirit rover from the martian sand trap that has held it for nearly 10 months, the unsuccessful outcome notwithstanding. The Jet Propulsion Laboratory-based team had been laboring since November to free Spirit with the aid of modeling and analysis tools and a test rover in a sandbox on the premises. But while they managed to move the rover ever so slightly in mid-January, controllers concluded soon thereafter it was time to throw in the towel, with Spirit having lost the function of two of its six wheels and the frigid martian winter approaching.
Spirit’s scientific instruments are still working, however, and NASA now plans to use it as a stationary research platform. The rescue effort has shifted to positioning Spirit to survive the winter, which entails altering its tilt so that its solar arrays have the best angle for absorbing the sun’s energy. Once this is accomplished, some of the Mars Exploration Rover personnel and resources that have been dedicated to the operation can be transferred to Spirit’s twin, Opportunity, which still has full mobility but has issues of its own, or to other activities.
NASA has gotten far more science out of Spirit and Opportunity than the agency could reasonably have expected. The relatively low-cost rovers, which arrived separately on Mars for what were supposed to be 90-day missions, have lasted six years. During that time, Spirit traversed some 21 kilometers of martian territory, taking pictures, analyzing soil samples and monitoring the atmosphere. From its stationary position — assuming it survives the winter — Spirit will carry on with activities that include studying martian wind and trying to determine whether the planet’s core is liquid or solid.
Even if it doesn’t survive, Spirit — like Opportunity — will stand as a tribute to the engineering skills, dedication and can-do attitude of NASA’s 150-person Mars Exploration Rover team.