James Cameron is in the Pacific for his dive to the deep ocean floor. What’s down there – way deep? We’ll explore.

This February 2012 photo, provided by National Geographic, shows explorer and filmmaker James Cameron emerging from the hatch of DEEPSEA CHALLENGER during testing of the submersible in Jervis Bay, south of Sydney, Australia. Earth's lost frontier, the deepest part of the oceans where the pressure is like three SUVs sitting on your little tow, is about to be explored first-hand. (AP)

Right now out on the Pacific, on a ship over the deepest ocean trench on the planet, director/explorer James Cameron is ready to dive.  Straight down, 36,000 feet – 6.8 miles – into the Mariana Trench, the “Challenger Deep.”  It is deeper than Mount Everest is high.  Beyond sunlight, beyond reach for the last half century, and beyond imagination for most of us.  The creatures.  The conditions.

This hour, On Point:  Top deep sea oceanographer Sylvia Earle and biologist Craig McClain take us where James Cameron is set to dive.

Plus, we’ll talk with the leader of the new hunt for Amelia Earhart.

-Tom Ashbrook

Guests

Sylvia Earle is explorer-in-residence at National Geographic and co-author of “Ocean: An Illustrated Atlas.”  A pioneering and record-setting deep diver, she has logged over 6,000 hours underwater and led more than 50 expeditions, including the first team of women aquanauts during the 1970 Tektite Project.

Craig McClain, assistant director of Science at the National Evolutionary Synthesis Center, jointly operated by Duke, the University of North Carolina at Chapel Hill, and North Carolina State University. He also runs the Deep Sea News blog.

C-Segment: Amelia Earhart

Ric Gillespie, executive director of The International Group for Historic Aircraft Recovery, he is leading an expedition to the South Pacific to search for wreckage of Earhart’s plane. You can read more on the story here.

Here’s the photo that triggered the new search:

This image provided by The International Group for Historic Aircraft Recovery and displayed at a U.S. State Department news conference on Tuesday, March 20, 2012, may provide a new clue in one of the 20th century's most enduring mysteries and could soon help uncover the fate of American aviator Amelia Earhart, who went missing without a trace over the South Pacific 75 years ago, investigators said. Enhanced analysis of a photograph taken just months after Earhart's Lockheed Electra plane vanished shows what experts think may be the landing gear of the aircraft, the small black object on the left side of the image, protruding from the waters off the remote island of Nikumaroro, in what is now the Pacific nation of Kiribati. Armed with that analysis by the State Department, historians, scientists and salvagers from The International Group for Historic Aircraft Recovery, are returning to the island in July 2012 in the hope of finding the wreckage of Earhart's plane and perhaps even the remains of the pilot and her navigator Fred Noonan. (AP)

From Tom’s Reading List

National Geographic: You can follow Cameron’s progress at the web site here.

Wired “What will this new breed of billionaire adventurers find?  What sorts of alien critters might we expect to see in Cameron’s upcoming documentary?”

New York Times “For centuries, the daredevils known as submariners have slipped beneath the waves in vehicles made for horizontal travel. Their craft are basically underwater ships. Even submersibles, small vessels that dive unusually deep, follow the horizontal plan.”

National Geographic “Squeezed into a submersible as futuristic as anything in his movies, James Cameron intends to descend solo to the ocean’s deepest point within weeks, the Canadian filmmaker and explorer announced Thursday. ”

Video: Mariana Trench Dive

This video from the National Geophysical Data Center simulates a dive into the deepest part of the world’s ocean.

Video: The First Deep Dive

This short video includes footage from the Bathyscaphe Trieste record-setting dive in 1960.

Video: Cameron’s Dive

This short promotional clip from National Geographic shows Explorer-in-Residence and Filmmaker James Cameron as he plans to dive to the Mariana Trench in the Pacific Ocean, earth’s deepest point.