Big Ideas: Harnessing Darkness To Produce LightAn electrical engineer from UCLA has created a prototype device that harnesses the darkness of the cold night sky to produce electricity. Chile’s Atacama Desert, which was once considered a "dead zone," is proving to be a promising place to search for antibiotics that could fight superbug bacteria. Plus, a new study says osteocalcin, a hormone secreted by our bones, may be responsible for our fight-or-flight response. And what would happen if the world's trees disappeared overnight? Read on to find out.