James Cameron's Dive Into the Mariana Trench

Filmmaker James Cameron gives two thumbs-up as he emerges from the Deepsea Challenger submersible, March 26, 2012, after his successful solo dive in the Mariana Trench, the deepest part of the ocean. The dive was part of Deepsea Challenge, a joint scientific expedition by Cameron, the National Geographic Society and Rolex to conduct deep-ocean research. (Mark Theissen/National Geographic)