Though Mars is currently a lifeless desert planet, that wasn’t always the case. Scientists have long suspected that Mars used to have an atmosphere thick enough to sustain vast liquid water oceans billions of years ago. NASA’s Curiosity rover has discovered some of the best evidence yet that supports the theory of Mars sustaining water for long periods of time. Because liquid water is an important precursor to life as we know it, this has some pretty impressive implications for the possibility of ancient life on Mars. The results span six papers, all of which appear in the December 9 issue of Science.
In the Yellowknife Bay in the Gale crater, Curiosity has been analyzing soil samples, collecting data about the geology and geochemistry of the area, in hopes of better understanding the past environment. This data will help researchers decide if ancient Martian life was plausible or not. After analyzing the chemical composition of the rocks, researchers were able to deduce that some of them had traveled great distances before experiencing erosion until much later. The mineral-rich clay that could have supported life was not localized near volcanoes, as there were not large amounts of trademark water soluble elements like calcium and sodium concentrated in those regions. The data suggests that these minerals were present and shuffled around for quite a while, but eventually did succumb to the drying environment and the increasingly hostile water conditions.