Mars Rover May Have Rolled to a Stop

Spirit

A Martian valley in it's actual natural coloring

The thick dust is scattered with rocks and minerals

The camera on Spirit's arm does a panoramic sweep, sending images back to earth.

NASA's Mars Rover, Spirit, has an uncertain future as it's sixth anniversary nears. Spirit attempted to turn all six wheels on Saturday, Dec. 26, 2009 to extricate itself from the sand trap known as "Troy," but stopped earlier than expected because of excessive sinkage.
Spirit will mark six years of unprecedented science exploration and inspiration for the American public on Sunday. However, the upcoming Martian winter could end the roving career of the beloved, scrappy robot.

Spirit successfully landed on the Red Planet at 8:35 p.m. PST on Jan. 3, 2004, and its twin robot, Opportunity arrived at 9:05 p.m. Jan. 24, 2004. The rovers began missions intended to last for only three months but which have lasted six Earth years, or 3.2 Mars years, in an amazing performance of exploring, charting and recording the great unknown. The little robots just kept going and going, like a very familiar pink rabbit. During this time, Spirit has found evidence of a steamy and violent environment on ancient Mars that was quite different from the wet and acidic past documented by Opportunity, which has been operating successfully as it explores halfway around the planet.

A sand trap and balky wheels are the challenges now to Spirit's mobility. They could prevent NASA's rover team from using a key survival strategy for the rover. The team may not be able to position the robot's solar panels to tilt toward the sun to collect power for heat to survive the severe Martian winter.

Nine months ago, Spirit's wheels broke through a crusty surface layer into loose sand hidden underneath. Efforts to escape this sand trap barely have budged the rover. The rover's inability to use all six wheels for driving has worsened the predicament. Spirit's right-front wheel quit working in 2006, and its right-rear wheel stalled a month ago. Drives with four or five operating wheels have produced little progress toward escaping the sand trap. The latest attempts resulted in the rover sinking deeper in the soil.
"The highest priority for this mission right now is to stay mobile," said Steve Squyres of Cornell University in Ithaca, N.Y. He is principal investigator for the rovers.

If mobility is not possible, the next priority is to improve the rover's tilt, while Spirit is able to generate enough electricity to turn its wheels. Spirit is in the southern hemisphere of Mars, where it is autumn, and the amount of daily sunshine available for the solar-powered rover is declining. Spirit's tilt, nearly five degrees toward the south, is unfavorable because the winter sun crosses low in the northern sky.
Unless the tilt can be improved or winds help prevent the gradual buildup of dust on the solar panels, the amount of sunshine available will continue to decline until May 2010. During May, or perhaps earlier, Spirit may not have enough power to remain in operation. The team is evaluating strategies for improving the tilt even if Spirit cannot escape the sand trap, such as trying to dig in deeper with the wheels on the north side. In February, NASA will assess Mars missions, including Spirit, for their potential science versus costs to determine how to distribute limited resources.

In 2004 the rover, Opportunity, discovered the first mineralogical evidence that Mars had liquid water. The rover recently finished a two-year investigation of a half-mile wide crater called Victoria and now is headed toward Endeavor crater, which is approximately seven miles from Victoria and nearly 14 miles across. Since landing, Opportunity has driven more than 11 miles and returned more than 132,000 images.

I hope they are granted enough money to keeps these little guys roving. I still can't believe the images I'm looking at are actually coming from Mars. There is so much more we need to learn about our giant red neighbor.