Digging up Pharaohs, Biofuels in the Sky, Lawrence Krauss on Why We're Here

Plus new technology for preserving organs, aviation fuel goes green and your question, answered.
An Egyptian woman walks past the head of a statue at the site of a new discovery by a team of German-Egyptian archaeologists in Cairo's Mattarya district on March 9, 2017. (KHALED DESOUKI/AFP/Getty Images)
Listen to the full episode53:51