Curiosity rover just found surprising storages of silica on Mars as it ventures higher on Mount Sharp. Curiosity is instrumental in understanding the changes that the environment and climate of the Red Planet have undergone through three billion years of existence.
In over three years of mission, Curiosity rover has brought brought about crucial insight on the geological composition of Mars, its atmosphere and other key scientific issues. Now, as NASA’s rover treks up Mount Sharp, it’s on to a new discovery that may pinpoint significant changes in what we know of the Red Planet.
Over three years ago, Curiosity rover landed in the 96-mile-wide Gale Crater. According to data gathered throughout the mission, this depression would have once housed lakes of fresh water. As it tracked across the Gale Crater, Curiosity rover sampled mostly basaltic rocks, a typical rock composition found on Mars. With the past months, the landscape is changing according to Ashwin R. Vasavada who is the project scientists with the Curiosity mission.
The meeting of the American Geophysical Union taking place in San Francisco last week saw Vasavada enthusiastically explaining the new framework of discussion. Although there are only hints and no final story yet.
3.6 billion years ago, Gale Crater was created when an asteroid hit Mars. The sediment that filled the crater afterwards was blown away by winds and eroded until Mount Sharp was created as a landmark towering over the depression. As Curiosity rover is moving higher and higher up Mount Sharp, each layer of sedimentary rock starts telling a different story about the geology of the Red Planet. And as it seems, Curiosity rover just found surprising storages of silica on Mars.
Silica represents a class of minerals in the composition of which oxygen and silicon reign high. Finding several types of silica indicates that liquid water was present and acting on the sedimentary rocks long after the lakes of fresh water disappeared. According to Vasavada, it was groundwater that filtered through the sedimentary rocks several times as pinpointed by the chemical signatures left behind.
Between basaltic rocks and mudstone rocks and sandstone rocks, Curiosity rover found that the latter two had 90 percent more silica than any of former analyzed so far. The first clue came as Curiosity rover reached Marias Pass. Marias Pass is and intersection of mudstone and sandstone at the base of Mount Sharp. There, in a light-tone bedrock NASA’s rover found the high levels of silica. The data was interpreted only later, so scientists drove Curiosity rover back to the scene after it had advanced further on Mount Sharp.
Heading back, the rover drilled into Buckskin, a rocky formation in the area and analyzed the chemical composition once more. With bets in place, the scientific team never expected that Curiosity rover would find tridymite, never before seen on Mars and certainly not in such a rocky formation. On Earth, it forms in volcanic rocks, but not in sedimentary rocks. Further analysis will bring a full exciting story on Curiosity rover’s latest discoveries.
Photo Credits: Wikimedia