According to Enrico Fermi, there's a high probability of extraterrestrial life, but we haven't found any yet. Why is that? Listen in as top scientists discuss the question of what and who else might be out there.

Featuring Adam Frank (University of Rochester), Louisa Preston (astrobiologist and author), Jason Thomas Wright (Pennsylvania State University), and Stephen M. Gardiner (University of Washington), with moderation by Ira Flatow (PRI's Science Friday ), this podcast features audio from the fifth event in our series, The Physics of Everything.