Getting the Mars Rover Unstuck

Some pics of scientists trying to figure out how to get the Opportunity Rover unstuck. Click on each image for details.

The mixture of sandy and powdery material brought in for these specific tests matched the way the soil underneath Opportunity caked onto wheels, filling the spaces between the cleats on the wheels.

UPDATE: Here's a more detailed press release from JPL.

UPDATE 2: They're almost ready to try a plan on Mars. They think it can be done:

We've learned quite a bit, and one of the things that we've learned is that it can take a lot of wheel turns to move the rover from a configuration like the one we're in.

(via Mars Rover Blog.)