Cameron is using a submarine to descend nearly seven miles to the bottom of the Mariana Trench in the Pacific. The pressure below is the equivalent of three SUVs sitting on your toe.
Director James Cameron began his journey Sunday to someplace only two men have gone before — to the Earth's deepest point.
The director of "Titanic," ''Avatar" and other films is using a specially designed submarine to descend nearly seven miles (11 kilometers) to the bottom of the Mariana Trench, an area 200 miles (320 kilometers) southwest of the Pacific island of Guam.
He began the dive at approximately 5:15 a.m. Monday, local time, according to Stephanie Montgomery of the National Geographic Society, where Cameron is an explorer-in-residence.
"RELEASE, RELEASE, RELEASE!" were the last words Cameron uttered before beginning the dive, according to a Twitter post from the expedition.
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The scale of the trench is hard to grasp — it's 120 times larger than the Grand Canyon and more than a mile (1.6 kilometers) deeper than Mount Everest is tall. It was expected to take Cameron 90 minutes to reach the bottom aboard his 12-ton, lime-green sub called "Deepsea Challenger." Once there, Cameron planned to spend six hours collecting samples for biologists and geologists to study. The return trip to the surface was forecast to take 70 minutes.
There's considerable wiggle room built in, however, as the submarine Cameron helped design has the capability to support life for a 56-hour dive.