Nature Podcast

This year, Nature celebrates its 150th birthday. To mark this anniversary we’re rebroadcasting episodes from our PastCast series, highlighting key moments in the history of science.In the early 1990s, a team of astrophysicists led by Carl Sagan looked at data from the Galileo spacecraft and saw the signatures of life on a planet in our galaxy. Historian of science David Kaiser and astrobiologists Charles Cockell and Frank Drake discuss how we can tell if there is life beyond the Earth – and how optimism, as well as science, is necessary for such a venture.This episode was first broadcast in October 2013.  See acast.com/privacy for privacy and opt-out information.