A submarine.
The DEEPSEA CHALLENGER sub in tests off Papua New Guinea in March.
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. (See more pictures of Cameron's sub.)
Just Tuesday, during testing off Papua New Guinea, Cameron dived deeper than any other human has on a solo mission. Now he aims to become the first human to visit the Mariana Trench's Challenger Deep in more than 50 years—and to return with animals, images, and data that were unthinkable in 1960.
That year the two-person crew of the U.S. Navy submersible Trieste—still the only humans to have reached Challenger Deep—spent only 20 minutes at the bottom, their view obscured by silt stirred up by the landing (more on the Trieste dive).
By contrast, the Cameron-designed DEEPSEA CHALLENGER sub is expected to allow the explorer to spend about six hours on the seafloor. During that time he plans to collect samples and film the whole affair with multiple 3-D, high-definition cameras and an 8-foot-tall (2.4-meter-tall) array of LED lights.
Designed to sink strangely—and efficiently—upright, the 24-foot-tall (7-meter-tall) craft was eight years in the making. Among its advances is a specially designed foam that helps allow the new sub to weigh in at 12 metric tons, making it some 12 times lighter than the Trieste.
Cindy Van Dover, a marine biologist at Duke University and a former pilot of the deepwater submersible Alvin, said she hopes some of DEEPSEA CHALLENGER's technology will trickle down to the rest of the deep-ocean science community.
"I think some of the engineering feats that have to be overcome are some of the most exciting aspects of this project ... because going to such extreme depths will require some technological breakthroughs," said Van Dover, who is not involved in Cameron's dive attempt.
Despite its innovations, the DEEPSEA CHALLENGER's spherical steel cockpit just barely accommodates its single occupant—in this case, Cameron, the man behind Avatar, Titanic, The Terminator, and, fittingly, The Abyss.
Nothing in his fictional worlds could quite prepare him for real-life exploration, said Cameron, a veteran of dozens of deep-sea submersible dives.
"When you're on an expedition, nature hasn't read the script, the ocean hasn't read the script, and no one knows what's going to happen next."
Retired U.S. Navy Capt. Don Walsh, who descended to Challenger Deep with Swiss engineer Jacques Piccard in the Trieste in 1960, said he was very pleased by the renewed interest in the Mariana Trench.
"I think it's about time," said Walsh, who is an advisor to the DEEPSEA CHALLENGE project and who will be with the Cameron team when the sub makes its Challenger Deep attempt.
"When Jacques and I surfaced from our deep dive, we were thinking about how long before someone else tries it, and we came to the conclusion that it would be about two years."
Mariana Trench Still a Mystery
Cameron and his team will head for the Mariana Trench only after completing more tests—this time off the U.S. island territory of Guam (map), about 200 miles (320 kilometers) northeast of Challenger Deep.
The dive will be part of Cameron's DEEPSEA CHALLENGE project, a partnership with National Geographic and Rolex that will take him and a crew of engineers, scientists, and filmmakers to the deepest ocean regions on Earth.
(Despite a claimed sighting by a Trieste crewmember, the presence of fish in Challenger Deep is very much an open question. So far no robotic mission has spotted fish there.)
"We're gonna go down there with our cameras, our lights, and find the answers to some of those questions," Cameron said.
The Mariana Trench is something of a 1,500-mile-long (2,550-kilometer-long) scar in the Pacific seafloor. (See pictures of the Mariana Trench region.)
At Challenger Deep, the trench plummets 6.8 miles (11 kilometers) down—if Mount Everest were dropped here, its summit would be more than a mile (1.6 kilometers) underwater. (Animation: Cameron's Mariana Trench dive compressed into one minute.)
"It's a place we can't get to, and we don't like not being able to get to places," Duke's Van Dover said. "It's something that gets to our psyche—we want to reach the impossible."
Because of its extreme depth, the trench is perhaps the most inhumane place on Earth: cloaked in perpetual darkness, chilled to near freezing. At the bottom, Cameron's craft will be subjected to water pressures approaching 16,000 pounds per square inch (1,125 kilograms per square centimeter).
"It would be about the equivalent of turning the Eiffel Tower upside down and resting it on your big toe," DEEPSEA CHALLENGE team member Patricia Fryer told National Geographic News. Fryer is a geologist at the Hawai'i Institute of Geophysics & Planetology (HIGP).
The sub will actually shrink by about 2.5 inches (6.3 centimeters) during the descent.
Expedition leader Cameron said, "Every single fastener, every single way of joining structures on the sub had to be looked at very carefully, because otherwise stainless steel bolts would just shear as the sub compressed."
Cameron isn't the only person dreaming of reaching the ocean's deepest point.
U.K. magnate Richard Branson has built a two-seater sub resembling a stubby-winged airplane, which he says can survive a Challenger Deep descent. Also, the Triton "luxury" submersible company last year unveiled the Triton 36000/3 model, which would reportedly allow a three-person crew to make the journey.
Of the current-day contenders, the DEEPSEA CHALLENGER looks as though it'll be first to the bottom—and of course first to return.
Once Cameron flips a switch, an electromagnetic system is to jettison the heavy steel plates that allow the DEEPSEA CHALLENGER to sink—sending the sub surfaceward like a cork.
The team estimates Cameron will be able to complete the descent in an hour and a half. The ascent should take about the same amount of time—a far cry from the Trieste's five-hour descent and three-hour-plus ascent.
The trip, though, won't be a comfortable one for Cameron.
In the 43-inch-wide (109-centimeter-wide) steel "pilot sphere," the explorer won't be able to extend his arms or legs. And he'll have to share that scant space with snacks, a camera, joysticks, and a change of warmer clothing (more on what Cameron will experience).
"It's like a clown car in there," Cameron said. "You barely have room to get in, and then they hand you another 50 pounds [23 kilograms] of equipment." (See inside the pilot sphere.)
Trieste co-pilot Walsh, who has seen the DEEPSEA CHALLENGER in person, said he was very impressed by its technology.
"When you look backward from when we dove ... it's like asking Orville Wright to compare his airplane to a 747," he said.
Nevertheless, when Cameron invited Walsh to sit in a mockup of the sub's cramped cockpit, he declined. "I just told him my body doesn't fold that way anymore."
"Totally Alien" Animals Await?
During the expected six-hour sea-bottom sojourn, Cameron will be able to use the DEEPSEA CHALLENGER's 12 propeller-driven thrusters to move up and down and side to side and to hover in place.
With a folding robotic arm, he'll be able to collect rocks, animals, and seafloor core samples for later study on the surface. (Related: "Life Is Found Thriving at Ocean's Deepest Point.")
Before Cameron's dive, the team also plans to send unmanned "landers" to the trench bottom. Resembling skinny phone booths, the 13-foot-tall (4-meter-tall), camera-equipped submersibles will carry bait to lure sea creatures into plastic cylinders, which can be retrieved by the team when the landers surface.
"The animals on the inside are captured" and even after ascent, "still cold, still under pressure," Kevin Hardy, senior development engineer at the Scripps Institution of Oceanography in San Diego, California, and a member of the DEEPSEA CHALLENGE team, told National Geographic.
Hardy predicts some of the specimens will be "totally alien" to scientists. "If you can imagine a wild animal, you'll find it down there."
Already, "science fiction is mimicking what we see for real in the deep ocean," he added. "And we haven't seen it all yet. There's a 'continent' we haven't explored down there."
Duke’s Van Dover is also excited about the scientific discoveries that could be lurking in the trench.
"Challenger Deep is one of those truly mysterious places where we're bound to discover many new species and different kinds of habitats that we haven't imagined before," she said.
"Many scientists would like to understand more about the pressure effects on physiology and biochemistry at those depths."
Why Send Cameron?
While many of the scientific goals Cameron hopes to achieve with the DEEPSEA CHALLENGER could be accomplished with an unmanned sub, he believes the risk is worth it.
Piloting a submersible remotely, "you just don't get a sense of that situational awareness that you have when you're really down there," he said.
HIGP's Fryer agreed, saying a remotely operated vehicle (ROV) is no substitute for sending a human-occupied vehicle into the abyss.
"It's like the difference between night and day," Fryer said.
"The critical thing is to be able to take the human mind down into that environment, to be able to turn your head and look around to see what the relationships are between organisms in a community and to see how they're behaving, to turn off all the lights and just sit there and watch and not frighten the animals so that they behave normally.
"That is almost impossible to do with an ROV."
Buried Secrets of the Mariana Trench
In addition to the rare specimens that could be brought back for study, scientists say a Mariana Trench dive could help shed light on natural disasters and even the emergence of life on Earth.
Most tsunamis, for example, result from earthquakes along faults called subduction zones, where one tectonic plate slowly slides beneath another, forming ocean trenches.
"What we've found by dredging the overriding plate on the inner slope of the [Mariana Trench] is that it exposes the upper part of the planet's mantle as well as the lower part of the Earth's crust and all the way up to the shallow crust," Fryer explained.
Close looks at such slopes could lead to a better understanding of the geological conditions that control earthquakes and provide valuable clues about the makeup of our planet.
Some scientists have also speculated that so-called mud volcanoes near the Mariana Trench could have served as incubators for the first life-forms on Earth. (See "Major Deep-Sea Smokers Found—'Evolution in Overdrive.'")
"The amino acids that are essential for building the earliest cells are not stable at high temperatures" such as those at volcanic vents along shallower ocean ridges, Fryer said.
For those crucial molecules, she said, "you'd need a relatively cool environment and you'd need water"—conditions present at Mariana Trench mud volcanoes.
"Of Course I'm Worried"
Cameron is well aware of the dangers involved in the Challenger Deep endeavor, and his team has built several safety precautions into the sub.
For example, if there's a power failure, the metal weights are to fall away, allowing the sub to surface. And if the weights don't disengage normally, a wire connecting them to the sub will corrode within about 12 hours.
Cameron will also have the option of using a heat-based method to break the bolts holding the plates—which furthermore can be electromagnetically disengaged via a signal from a research vessel at the surface.
Even with multiple safeguards, Cameron isn't exactly carefree.
"Yeah, of course I'm worried," he said. "Worry is a good thing when you're an explorer.
"I think when you're cavalier, when you take risk for granted—that's when you're going to get bitten."
Rachael Jackson of National Geographic Channels International contributed reporting to this story.
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