"So far, the materials Curiosity has analyzed are consistent with our initial ideas of the deposits in Gale Crater, recording a transition through time from a wet to dry environment," added David Bish of Indiana University in Bloomington, co-investigator on the CheMin experiment. "The ancient rocks, such as the conglomerates, suggest flowing water, while the minerals in the younger soil are consistent with limited interaction with water."
Indeed, MSL scientists know that Curiosity has landed in an ancient dry riverbed, providing us with a huge advantage in the pursuit of understanding the wet past of Mars and its potential for harboring habitats suitable for (past or present) microbial life.
Curiosity will now drop a sample of soil into another instrument - the Sample Analysis at Mars (SAM) instrument - to assess whether the dust and sand at Rocknest contain organic carbon-based compounds that may reveal the planet's potential for supplying the building blocks of life.
Source: JPL News
Image: The first analysis of X-ray diffraction on Martian soil by the Chemistry and Mineralogy (CheMin) experiment. The soil sample, taken from a wind-blown deposit within Gale Crater, where the rover landed, is similar to volcanic soils in Hawaii. Credit: NASA/JPL-Caltech/Ames