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Diving Back To The Bottom Of The Mariana Trench

Robert Siegel talks to retired Navy Captain Don Walsh about the attempt by movie director James Cameron to take a submersible capsule to the bottom of the Mariana Trench — the deepest spot on Earth. Walsh says the National Geographic and James Cameron expedition will be a combination of science and adventure, because Cameron is a storyteller and dedicated amateur explorer. Walsh made a 1960 dive to the same trench.