NASA's Mars rover Curiosity dug up five scoops of sand from a patch nicknamed "Rocknest." A suite of instruments called SAM analyzed Martian soil samples, but the findings have not yet been released.
Roger Angel, an astronomer at the University of Arizona, stands in front of his new project: a solar tracker. Angel wants to use the device to harness Arizona's abundant sunlight and turn it into usable energy.
Jason Millstein for NPR