A spacecraft orbiting Mars photographed one of NASA’s rovers and its tracks on the surface, the space agency said Monday. The image made by a camera aboard the Mars Global Surveyor shows a dark dot identified as the rover Spirit next to giant Bonneville Crater and the thin dark line of its tracks leading back to its lander. The picture was made by rolling the entire spacecraft, adjusting its rotation rate to match the ground speed under the camera, a process that produces sharper images.