The latest view from Mars is of a large out-cropping near Opportunity that shows some layers that NASA scientists are very interested in.

"Geologists said that the layers -- some no thicker than a finger -- indicate the rocks likely originated either from sediments carried by water or wind, or from falling volcanic ash. "We should be able to distinguish between those two hypotheses," said Dr. Andrew Knoll of Harvard University, Cambridge, a member of the science team for Opportunity and its twin, Spirit. If the rocks are sedimentary, water is a more likely source than wind, he said."