Images From Mars
16 Mar 2004
(Source: Jet Propulsion Laboratory)
Drifts of Dust or Something Else?
Press Release Image: Spirit
March 16, 2004
While the interior and far walls of the crater dubbed "Bonneville" can be seen in the background, the dominant foreground features in this 180-degree navigation camera mosaic are the wind-deposited drifts of dust or sand. NASA's Mars Exploration Rover Spirit completed this mosaic on sol 71, March 15, 2004, from its newest location at the rim of "Bonneville" crater.
Scientists are interested in these formations in part because they might give insight into the processes that formed some of the material within the crater. Thermal emission measurements by the rover indicate that the dark material just below the far rim of this crater is spectrally similar to rocks that scientists have analyzed along their journey to this location. They want to know why this soil-like material has a spectrum that more closely resembles rocks rather than other soils examined so far. The drifts seen in the foreground of this mosaic might have the answer. Scientists hypothesize that these drifts might consist of wind-deposited particles that are the same as the dark material found against the back wall of the crater. If so, Spirit may spend time studying the material and help scientists understand why it is different from other fine-grained material seen at Gusev.
The drifts appear to be lighter in color than the dark material deposited on the back wall of the crater. They might be covered by a thin deposit of martian dust, or perhaps the drift is like other drifts seen during Spirit's journey and is just a collection of martian dust.
To find out, Spirit will spend some of sol 72 digging its wheels into the drift to uncover its interior. After backing up a bit, Spirit will use the panoramic camera and miniature thermal emission spectrometer to analyze the scuffed area. If the interior material has a similar spectrum to the dark deposit in the crater, then Spirit will most likely stay here a little longer to study the drift with the instruments on its robotic arm. If the material is uniform - that is, dusty all the way down, Spirit will most likely move off to another target.
Opportunity Studies Bait in Shark's Cage
Press Release Image: Opportunity
March 16, 2004
In its 49th sol on Mars, NASA's Opportunity had nearly concluded its scientific examination of the extreme southwestern end of the outcrop in Meridiani Planum. In the "Shark's Cage" area of the neighborhood called "Shoemaker's Patio," featured in this image from the front hazard avoidance camera, Opportunity deployed its arm to study the features called "Shark's Tooth," "Shark Pellets," and "Lamination." "Shark's Tooth" is a piece of the unusual red rind that appears to fill cracks in the outcrop. This rind may be some kind of chemical alteration of the rocks. "Shark Pellets" is an area of soil that was under investigation as part of the crater soil survey. "Lamination" is a target with very thin layers that resemble uniform pages in a book, an indication of how the sediments were deposited. A final experiment in this area will be attempted on sol 51. Opportunity's front left wheel will "scuff" the rock called "Carousel." "Scuffing" involves scraping the rock with one wheel while holding all the others still. This experiment essentially turns the rover wheels into tools, to try and determine the hardness of the target rock.