The "after" image was taken after about seven minutes of shaking a sample of Martian soil, which rests on a screen over the opening to one of the eight ovens of the Thermal and Evolved-Gas Analyzer instrument on Phoenix. The soil resting on the screen has slumped almost imperceptibly downhill, with a dark gap about 3 millimeters (one-tenth of an inch) wide opening at the top edge of the screen. Credit: NASA/JPL-Caltech/University of Arizona/Max Planck Institute
