Support WBURNASA is bringing rocks back from Mars, but what if those samples contain alien life?Play03:40Download AudioNell GreenfieldboyceMay 04, 2022 ShareNASA's Perseverance rover took this "selfie" next to a rock where it drilled for samples. NASA wants to bring samples collected by this rover back to Earth. (NASA/JPL-Caltech/MSSS)
