For centuries, philosophers, poets, and scientists alike have dreamed about planets similar to Earth circling other stars like our Sun. Lecture was at the Harvard-Smithsonian Center for Astrophysics. The talk starts at about 17 minutes into the video clip. The beginning as Dave Aguilar talking about what's up in the night sky in preparation for star gazing after Andree's talk. Movie format is RealPlayer.

Credit: Harvard Smithsonian Center for Astrophysics