At a rock called "Clovis," the rock abrasion tool on NASA's Mars Exploration Rover Spirit cut a 9-millimeter (0.35-inch) hole during the rover's 216th martian day, or sol (Aug. 11, 2004). The hole is the deepest drilled in a rock on Mars so far. This approximately true-color view was made from images taken by Spirit's panoramic camera on sol 226 (Aug. 21, 2004) at around 12:50 PM local true solar time–-early afternoon in Gusev Crater on Mars. To the right is a "brush flower" of circles produced by scrubbing the surface of the rock with the abrasion tool's wire brush. Scientists used rover's Mössbauer spectrometer and alpha particle X-ray spectrometer to look for iron-bearing minerals and determine the elemental chemical composition of the rock. This composite combines images taken with the camera's 600-, 530- and 480-nanometer filters. The diameter of the hole cut into the rock is 4.5 centimeters (1.8 inches). Image credit: NASA/JPL/Cornell.
Planetary scientists got excited when they saw this imagery coming in from NASA's Mars Exploration Rover Spirit because they could see hints of rock strata and other interesting geologic features ahead. In the middle of this image, from upper left to the lower right, lies a trough that resembles a small ravine. To the right of that and a little way up the hill, beyond a rock-strewn surface, sits a small rounded ridge. Fine horizontal streaks, just perceptible in this image, suggest possible layering in the bedrock. Above that are rock features that appear to drape across the slopes. Scientists are discussing whether to take the rover closer or select other interesting targets for further study. This view looks eastward from the "West Spur" of the "Columbia Hills," where Spirit has been conducting scientific investigations. It is a mosaic of several frames Spirit took with its panoramic camera on the rover's 229th martian day, or sol, (Aug. 24, 2004). The field of view is 48 degrees from left to right. The image is presented in a cylindrical projection with geometrical seam correction. Image credit: NASA/JPL/Cornell.
The intriguing dunes at the bottom of "Endurance Crater" presented a tantalizing target for the science team for NASA's Mars Exploration Rover Opportunity. After analyzing the soil near and around the dunes, however, the rover engineering team decided that it was too risky to send Opportunity any closer. The terrain between the rover and the dune tendril did not present clear evidence of rocky plates to give the rover sufficient traction. A finger-like dune tendril pictured here (left) is, essentially, pointing to the rover's current area of investigation. Opportunity rolled over the foreground rock, called "Puffin." During the past several sols the rover has been examining its new neighborhood, an area that includes the rocks "Ellesmere" and "Escher" (not pictured) and the soil targets "Shag" and "Auk" (also not pictured). Experiencing significant slippage, the rover did some unintended trenching and left deep tracks in this area. This view is a mosaic of two images taken by the rover's navigation camera on Opportunity's 206th sol on Mars (August 22, 2004) and presented in a cylindrical projection. Image credit: NASA/JPL.
The wheel tracks in this image are an artifact of the difficult terrain faced recently by NASA's Mars Exploration Rover Opportunity deep inside "Endurance Crater." Opportunity took the picture with its navigation camera on the rover's 205th martian day, or sol (Aug. 21, 2004). On the preceding sol, to avoid a potentially hazardous rock target, the rover team changed routes. Steep slopes and lack of traction when driving in this terrain caused the rover to experience up to 50 percent slip during parts of its traverse. Opportunity ended up more than 50 centimeters (about 20 inches) downslope from the planned final position. Another shift in objective on sol 205 had Opportunity on the move again toward safer terrain. Analysis of the final drive showed the rover's traction increasing during its latest moves. Image credit: NASA/JPL. Additional articles on this subject are available at: