Although they’re not so much in the news these days, the Martian rovers, Spirit and Opportunity are still hard at work on their primary mission: discovering evidence of past water on Mars. A new patch of soil uncovered by Spirit is so rich in silica, that scientists think that water must have helped concentrate it eons ago.
While it was exploring a region of hills inside Gusev crater, Spirit uncovered a patch of soil that was clearly different from the surrounding environment. Further examination by the rover’s alpha particle X-ray spectrometer calculated that it was more than 90% pure silica.
This concentration of silica would have required some process involving water. One theory is that the soil might have interacted with acid vapours produced by volcanic activity in the presence of water. Another possibility is that the region might have had many hot springs.
Scientists are celebrating the discovery as one of the most conclusive pieces of evidence for past water that the rovers have turned up so far.
Original Source: NASA/JPL News Release