The Mars Exploration Rover Spirit acquired this navigation camera image on the 72nd martian day, or sol, of its mission (March 15, 2004), after digging its wheel into the drift dubbed "Serpent." Creating the commands that would generate this "scar" was not an easy task for rover controllers. Essentially, they had to choreograph an intricate dance for Spirit, maneuvering it up the side of the dune, shimmying its left front wheel a number of times to create the scuff, and then reversing to attain proper positioning for miniature thermal emission spectrometer observations. Before the task was finished, Spirit moved forward...
