The geek chronicles

The Mars rovers Spirit and Opportunity have already far exceeded all expectations and intentions. They landed on opposite sides of Mars in January, 2004 for 90-day missions. It's now about 13 months past that point and they are still going. But things are getting sticky - or actually, loose. And that's the problem.

The Mars rover Opportunity is facing its biggest challenge since it landed on the Red Planet last year: how to get out of a sand dune where it's been stuck for two weeks.

Engineers spent this week simulating the Martian terrain at NASA's Jet Propulsion Laboratory in Pasadena to try to figure out why the robot got bogged down and how to get it moving again. Engineers performed several tests driving a dummy rover over a man-made sand dune. ...

The six-wheeled Opportunity had driven about 130 feet of a planned 295-foot trip when its wheels started to slip April 26. The rover, going backward at the time, eventually stopped moving - its wheels stuck hub deep in fine soil while trying to drive over a foot-high sand dune.

This "major surprise" has for the moment limited Opportunity to taking pictures of its immediate surroundings. They will provide additional data, but not as much as continuing the trip would have.

The problem was undoubtedly extra frustrating because it came just a couple of days after Spirit failed in its attempt to climb a low hill. "[T]he most difficult terrain encountered so far" on Mars by either rover caused the wheels to slip "[l]ike a hiker walking on loose scree." NASA is trying to see if another approach can be found.

For info about the rover missions, including news and pictures, go here. For information about all Mars missions present and planned, the place is here.