Opportunity's "Underbelly" - Sol 1890

Caption NASA:"Similar to a geologist's hand lens, the Microscopic Imager (MI) on NASA's Mars Exploration Rovers is designed to image objects at a close distance (less than a few centimeters) at very High Resolution. On Sol 1890 (such as May 18, 2009) the Opportunity Rover used its MI Camera to take a picture of its underside.
While out of focus (as expected for this distance), the image does show the Rover Wheels (left middle and left rear), the ground and the "Underbelly" of Opportunity. This information may prove helpful for extracting Spirit's Wheels from the soft Martian Soil it has encountered and might be a way to see whether Spirit's belly pan is touching the rocks beneath it".