Spinning its wheels...

and going nowhere fast, the Mars Exploration Rover Spirit, that is. The view above (click to enlarge) is captured by the navigation camera, and looks back at its tracks made in April of this year, the last time the robotic explorer made any forward progress. Here's the latest from NASA/JPL on attempts to free the stuck rover.

Perhaps most significantly, the rocks scattered about appear to be laminated/bedded, and perhaps sedimentary in origin.