ALT This color image taken by Mastcam-Z on NASA's Perseverance Mars Rover shows a very noticeable light-toned boulder with dark speckles in a field of darker ones. Some on the science team speculate that the boulder's minerals were produced in a nearby subsurface magma sea that then bubbled to the surface where they cooled and solidified. Others consider the possibility that it could have been created far beyond the walls of Jezero and transported there by the swift Martian waters that flowed through this channel eons ago. Either way, the team believes this boulder is the first of its kind they’ve seen and won’t be the last as the rover travels further along the crater rim.