NASA has heaped on the folksiness. It treats the vehicles like plucky characters, and when the Spirit eventually reached one of its targets - a triangular football-size rock - NASA gave the rock a name, Adirondack, and photographed it from every point of view: at a distance, up close, from the side, from above. But from my point of view, the most intriguing picture, taken in black and white by the microscopic imager, was the strangest, a close-up that showed only one facet of the rock, half in brilliant sun, half in the shadow of the rover. Why? Because it didn't look like an Earth rock.