Lecture 39: The Drake Equation

How many intelligent, communicating civilizations live in our Galaxy? We have no idea. One way to approach the question and come up with quasi-quantitative estimates is the Drake Equation, first introduced by radio astronomy Frank Drake in the 1960s. I will use the Drake equation as an illustration of the issues related to the question of extraterrestrial intelligence, and to set the stage for future lectures on the likelihood of finding other intelligences in our Universe. Recorded live on 2009 Nov 23 in Room 1005 Smith Laboratory on the Columbus campus of The Ohio State University.