So the obituaries for the Mars rover Spirit are a bit premature, says rover scientist Ray Arvidson of Washington University, who I caught up with in the hallway here at LPSC. Since NASA headquarters held a press conference at the end of January announcing that Spirit would become a stationary science lander, the rover got itself unstuck and moved 34 centimeters using a sort of lateral ice-skating-like blading action. “We only stopped because we had to get ready for winter,” Arvidson said.
Arvidson said that the gimpy rover is still doing good stuff. He showed evidence for a soil profile of sulfate rich, water-soluble minerals. The most soluble ones are at the bottom of the profile – a sign that liquid water has acted gravitationally. Arvidson is also seeing the layered profiles match the wind-swept contours of the land. That suggests that the action of water is quite recent (geologically speaking) – probably about 100,000 years ago, the last time that Mars’ axis tilted enough to bring ice and frost down to the lower latitudes where Spirit roamed.
Arvidson acknowledges that Spirit will not be a “race car” again, but wants to look for similar soil profiles nearby. He says moving small distances would not jeopardize the radio science that is supposed to be the new priority with the rover acting as a science station.
Will the team get the money to keep all the engineers and drivers employed? The Mars budget is under significant duress as NASA struggles to pay for the shocking cost overruns of the Mars Science Laboratory, due for 2011 launch. Arvidson is waiting for the outcome of a ‘senior review’ of ongoing Mars missions to see how the most science per dollar can be extracted from Spirit’s tired robotic wheels.