This graphic shows results of the first analysis of Martian soil by the Chemistry and Mineralogy (CheMin) experiment on NASA’s Curiosity rover. The image reveals the presence of crystalline feldspar, pyroxenes and olivine mixed with some amorphous (non-crystalline) material. The soil sample, taken from a wind-blown deposit within Gale Crater, where the rover landed, is similar to volcanic soils in Hawaii. Curiosity scooped the soil on Oct. 15, 2012, the 69th sol, or Martian day, of operations. It was delivered to CheMin for X-ray diffraction analysis on October 17, 2012, the 71st sol. By directing an X-ray beam at a sample and recording how X-rays are scattered by the sample at an atomic level, the instrument can definitively identify and quantify minerals on Mars for the first time. Each mineral has a unique pattern of rings, or “fingerprint,” revealing its presence. The colors in the graphic represent the intensity of the X-rays, with red being the most intense. Image credit: NASA/JPL-Caltech/Ames
The minerals were identified in the first sample of Martian soil ingested recently by the rover. Curiosity used its Chemistry and Mineralogy instrument (CheMin) to obtain the results, which are filling gaps and adding confidence to earlier estimates of the mineralogical makeup of the dust and fine soil widespread on the Red Planet.
The identification of minerals in rocks and soil is crucial for the mission’s goal to assess past environmental conditions. Each mineral records the conditions under which it formed. The chemical composition of a rock provides only ambiguous mineralogical information, as in the textbook example of the minerals diamond and graphite, which have the same chemical composition, but strikingly different structures and properties.
CheMin uses X-ray diffraction, the standard practice for geologists on Earth using much larger laboratory instruments. This method provides more accurate identifications of minerals than any method previously used on Mars. X-ray diffraction reads minerals’ internal structure by recording how their crystals distinctively interact with X-rays.
These NASA technological advances have resulted in other applications on Earth, including compact and portable X-ray diffraction equipment for oil and gas exploration, analysis of archaeological objects and screening of counterfeit pharmaceuticals, among other uses.
Source:
SciTechDaily
