Rating is available when the video has been rented.
This feature is not available right now. Please try again later.
Uploaded on Jun 27, 2008
LISTEN TO FULL AUDIO: http://tinyurl.com/5ekcqf Tyson is the director of the Hayden Planetarium at the American Museum of Natural History and host of NOVA scienceNOW. Here he answers reader questions and talks about the universe and how he'd save the world.