Journey to the Bottom of Mariana Trench

James Cameron talks with his crew in front of the DEEPSEA CHALLENGER following testing of the submersible in Jervis Bay, south of Sydney, Australia. The submersible will travel to the bottom of the Mariana Trench as the centerpiece of DEEPSEA CHALLENGE, a

Crews prepare DEEPSEA CHALLENGER for its first test in the ocean at Jervis Bay, south of Sydney, Australia. (Photo: Mark Thiessen/National Geographic)

After their successful nine-hour dive in January 1960 to the bottom of the Mariana Trench, Don Walsh and Jacques Piccard emerge from the bathyscaphe Trieste. James Cameron will attempt to make only the second successful manned descent to this deepest part

James Cameron (left) and Don Walsh talk with filmmakers and explorers Mike deGruy (middle) and Andrew Wight, who were killed in a helicopter crash in Australia in February. The DEEPSEA CHALLENGE team will honor DeGruy and Wight’s memory by moving forward

James Cameron inside the pressure sphere simulator at Acheron Project offices in Sydney, Australia. (Photo: Brook Rushton)

DEEPSEA CHALLENGER is lowered into the water for testing off the coast of Australia. (Photo: Mark Thiessen/National Geographic)

Crews examine the DEEPSEA CHALLENGER aboard the Mermaid Sapphire off the coast of Australia. (Photo: Mark Thiessen/National Geographic)

Crews continue in-water testing in Australia of DEEPSEA CHALLENGER. (Photo: Mark Thiessen/National Geographic)

The DEEPSEA CHALLENGER begins its first 2.5-mile test dive off the coast of Papua New Guinea. (Photo: Mark Thiessen/National Geographic)

Crews continue in-water testing in Papua New Guinea of DEEPSEA CHALLENGER. (Photo: Mark Thiessen/National Geographic)

Swinging above the docks in Guam’s Apra Harbor is the Trieste, the submersible that took Don Walsh and Jacques Piccard on the first and only successful manned dive to the bottom of the Mariana Trench. (Photo: Thomas J. Abercrombie)

Jacques Piccard and Don Walsh emerge from the bathyscaphe Trieste following their successful manned descent to the bottom of the Mariana Trench in January 1960. (Photo: Thomas J. Abercrombie)