“I just sat there looking out the window, looking at this barren lunar plain and appreciating it,” he told reporters, following the trip, which was funded by the National Geographic Society, Rolex, and the Alfred P. Sloan Foundation.
Cameron's trip marks first solo dive to the Challenger Deep, and only the second visit by humans. In 1960, the US Navy sent the submersible Trieste and its two-man crew to the bottom there.
More trips are in the offing this year by various groups aiming to take people into the Challenger Deep or other parts of the Mariana Trench. These efforts include Sir Richard Branson's Virgin Oceanic sub, which like Cameron's Deepsea Challenger, is a single-seater. Several of the marine scientists who have worked with Cameron also are working with Mr. Branson's group.
Although deep-sea trenches make up only about 1 percent of the sea floor, they are of keen scientific interest. They form as old, dense oceanic crust, long ago made by lava welling up along mid-ocean volcanic ridges, now is pushed beneath more-buoyant continental crust.
The process creates a long, canyon-like boundary. The Mariana Trench, for instance, has an average width of about 43 miles but narrows to a slot-like valley at the bottom, nearly 7 miles below the ocean surface.
With crushing water pressure – roughly 1,000 times air pressure at sea level – and temperatures hovering around freezing, the environment at the bottom of these trenches is home to an unusual assortment of creatures. Last summer, for instance, a team from the Scripps Institution of Oceanography in La Jolla, Calif., and the National Geographic Society found that a super amoeba – a single-cell organism measuring about 4 inches across – was inhabiting depths two miles deeper than previously believed.