This image from NASA's Mars Odyssey spacecraft shows the checkerboard region of Noctis Labyrinthus, the Labyrinth of Night. Scientists think it began to develop when volcanic activity stirred in the adjoining region of Tharsis, stretching the crust and fracturing it. As cracks and faults opened, ice and water in the subsurface escaped, making the ground collapse. The result is a tangle of tablelands cut by canyons, troughs, and pits. This false-colour Thermal Emission Imaging System (THEMIS) mosaic focuses on one junction where canyons meet to form a depression 4 kilometres deep. This data can tell scientists about the nature of the materials on the ground. Dark streaks mark the paths of sand or dust avalanches. At the foot of the slope lie the traces of older, more substantial avalanches that piled up rocks and large debris.
© National Aeronautics & Space Administration / Science & Society