On Alien Encounters, scientists ask: "are we really alone in the universe?" And "what happens if we aren't?" In this 10-part series, astronomers, engineers and other experts will walk listeners through the real-life scenarios of what could happen if aliens landed on Earth, based on the research. Find out how aliens could make first contact and what they might do when they get here from experts like Neil DeGrasse Tyson, Nick Sagan, and members of SETI and NASA.