Red Soil, Rock Garden
The first color wallpaper image has arrived in the latest downlink from Mars. The smooth surfaces of angular and rounded rocks seen in the first color images of the martian terrain at Gusev crater may be the result of wind-polishing debris.
|A section of the large color panorama from the Mars Spirit pancam. Large image [2 Mb]|
Using the three instruments that look to analyze the composition of rocks and soils, scientists may use them to look for evidence such as:
- Weathering. Interaction with water can alter the chemical composition of rock-forming material. The water’s temperature affects those changes. Information from the spectrometers could thus provide evidence about the wetness and temperature of the past environment, two key factors in whether that environment was hospitable to life.
- Evaporites. Some minerals are formed when dissolved salts get left behind as water evaporates. Finding and identifying any "evaporite" minerals at Gusev would suggest that the crater once held a salty, shallow lake.
- Carbonates. Carbonate minerals, such as limestone, can form from chemical reactions that pull carbon dioxide out of the atmosphere into bodies of water. If Spirit’s spectrometers identify carbonate rocks, images from the rover’s cameras could yield clues about how long the environment stayed wet and whether water was in the form of hot springs.
Wheels of the rover, in addition to providing mobility, may be used to dig shallow trenches to evaluate soil properties and expose fresh soil to be examined. A small trench or scratch on the surface has already been imaged from a soil abrasion left when the rover’s airbags were pulled in. The engineers are preparing for egress and departure from their landing petal in a little more than a week.
JPL, a division of the California Institute of Technology, manages the Mars Exploration Rover project for NASA’s Office of Space Science, Washington, D.C.