MARS SCIENCE LABORATORY MASTCAM OBSERVATIONS OF GALE CRATER

The Mastcams were deployed on the remote sensing mast on the second Mars day after the successful landing of the MSL rover. Consisting of two cameras, each with a 1600 x 1200 detector, with focal lengths of 34 mm (left, 220 µrad IFOV) and 100 mm (right, 74 µrad), the Mastcam pixel scales are 22 cm and 7.4 cm at 1000 m. Both cameras acquire broadband color and, using narrowband filter wheels, multi-spectral images.

The regolith at the landing site is poorly sorted debris with about 50% of the surface area consisting of unresolved fines and 50% of 1-4 cm gravel. Approximately 90% of the pebble and cobble population consists of angular to sub-angular fragments. Immediately north of the rover, the Main Landing Engines uncovered a clast-rich layer immediately below the gravel veneer, consisting of pebbles and cobbles to 12 cm diameter, some rounded. Although the majority of stones appear superposed on the gravel, some are embedded in the substrate. Large rocks are rare near the lander, but more abundant in the far field. Rocks of several different lithologies are seen, denoted by tone, texture, and fracture nature. Intermediate-toned, smooth-surfaced angular stones show evidence of wind abrasion. The lower few cm of some of the rocks display a light-toned, reddish stain or patina. Although the site is close to a large dune field, eolian bedforms and windtails associated with rock obstacles are not seen near the lander. No small-scale scarps or channels are visible from the landing site, although small, shallow depressions are seen near the lander that may be impact craters. Larger scale geomorphic features include impact craters, buttes and mesas associated with the erosion of sedimentary beds, the dune field south of the landing site, and the valley networks on the north crater wall. Stratigraphic relationships within the layered units of Mount Sharp are only weakly visible in the M-34 frames but are much better detailed in the M-100 frames.

Co-authors of this work include: J Bell, W Dietrich, K Edgett, L Edwards, J Garvin, B Hallet, K Herkenhoff, E Heydari, L Kah, M Lemmon, J Maki, M Minitti, T Olson, T Parker, K Rowland, R Sletten, J Schieber, R Sullivan, D Sumner, P Thomas, A Yingst, M Ravine, M Caplinger, E Jensen, and S McNair.