Ocean explorer Robert Ballard takes us on a mindbending trip to hidden worlds underwater, where he and other researchers are finding unexpected life, resources, even new mountains. He makes a case for serious exploration and mapping. This is a 2008 presentation, but still very much worthwhile. If you wish to watch a recent, 54 minute presentation watch Robert Ballard give a lecture to High School students at George Washington University. Really great lecture! A+ www.youtube.com Also see Robert Ballard's education site www.jason.org