For about six months, NASA’s Curiosity Mars rover has been exploring a region full of geologic formations called boxwork, low ridges standing roughly 3 to 6 feet (1 to 2 meters) tall with sandy hollows in between. Crisscrossing the surface for miles, the formations suggest ancient groundwater flowed on this part of the Red Planet … Continue reading NASA’s Curiosity Rover Sees Martian ‘Spiderwebs’ Up Close