This mosaic of images from the Surface Stereo Imager camera on NASA's Phoenix Mars Lander shows several trenches dug by Phoenix, plus a corner of the spacecraft's deck and the Martian arctic plain stretching to the horizon.
The footpad at the bottom center is about 3 feet (1 meter) below the spacecraft deck seen at the lower left. Overlaid images show trenches dug to either nearly pure water ice or ice-cemented soil. Analyses of samples taken from these trenches give clues to the history of the region.
NASA/JPL-Caltech/University of Arizona/Texas A&M University