Before setting his sights once again on the far-off moon Pandora for the next Avatar adventure, filmmaker and aquanaut James Cameron has bequeathed arguably his greatest technological accomplishment to science. Cameron’s DEEPSEA CHALLENGER submarine, which he drove to the deepest part of this planet last March, will in June arrive at Woods Hole Oceanographic Institution (WHOI) in Massachusetts, ultimately helping researchers there better understand life in Earth’s last unexplored frontier.

“Most of what’s known about the bottom of the ocean has come from images shot miles up in the water column, and it’s a relatively coarse data set,” Cameron said recently at roundtable discussion in New York City with WHOI scientists who design, build and operate manned and robotic deep-sea exploration vehicles. “So you’ve got to get down there and look around and ground-truth it,” he added. “Very little of that looking around has been done.”

Cameron and his team of engineers outfitted the DEEPSEA CHALLENGER with cutting-edge flotation mechanisms and energy storage systems, along with cameras, lighting and other features specifically tailored for gathering data, samples and images during the first manned mission to the deepest recess of the Mariana Trench. He touched down about 11 kilometers below the Pacific Ocean surface at the Challenger Deep site, a spot previously visited by only a handful of robotic subs. During the seven-hour round-trip, Cameron spent about three hours at Challenger Deep collecting samples for marine biology, microbiology, astrobiology, marine geology and geophysics research.

In addition to the DEEPSEA CHALLENGER itself, Cameron is kicking in nearly $1 million to help WHOI scientists and engineers make the sub's technology more widely available for deep-sea exploration. “We’ve been be sure to fund this enough that there are enough people and resources available to write this up, publish it and therefore have it available,” he said. “To me, that’s an infinitely better outcome than [the sub] sitting dormant until I’m done with my next two movies, and maybe it comes to the tech community five or six years down the line when it’s already obsolete.”

Most immediately WHOI scientists will install lightweight, highly maneuverable cameras and a lighting system that Cameron and his team designed for the DEEPSEA CHALLENGER onto the institute’s Nereus robotic sub, which has been exploring the oceans’ depths since 2009. The Nereus team is preparing for a six-week voyage—funded by the National Science Foundation to the tune of about $1.4 million—beginning in February 2014 to study the Pacific Ocean’s Kermadec Trench, which is about 10 kilometers deep. The DEEPSEA CHALLENGER's camera equipment and lighting enabled Cameron to capture high-resolution 3-D images of geologic processes and species despite the pitch-black depths during his dives, including the Challenger Deep expedition and a number of test dives.

Scientists want to explore every aspect of oceanography in the deep-water hadal regions—those anywhere below a depth of six kilometers. Researchers want to know what lives there, understand the food supply for its denizens and how they evolved, Tim Shank, an associate scientist in Woods Hole’s Biology Department, said at the event. Shank is the leader of the Hadal Ecosystem Studies (HADES) project investigating the major environmental drivers of trench ecology. Biology in the ocean’s hadal regions is largely unknown, and much of what scientists do know is the result of Danish and Soviet sampling expeditions in the 1950s, Shank added.

Everything changes below six kilometers, and the next generation of research subs need to be built with that in mind, Cameron said. Vehicles that can withstand the extreme pressure at those depths tend to be heavier and more difficult to manage, making them more expensive and less fuel-efficient. Cameron’s engineers actually developed new materials—including a syntactic foam made from millions of hollow glass microspheres suspended in an epoxy resin—to strengthen the sub’s hull without adding a lot of weight. The vessel, which is 7.3 meters long but only 1.09 meters wide, also has a sphere-shaped pressurized cockpit that collected evaporated moisture from Cameron’s breath and sweat into a plastic bag, which would supply him with extra drinking water if necessary. The vessel itself descends vertically, with the cockpit oriented at the bottom, below a 2.4-meter-long panel of lights and batteries.

The sub will arrive at WHOI shortly after the opening of the institution’s new Center for Marine Robotics (CMR), which seeks to develop marine exploration technology with help from academia, the federal government and businesses. Such technology has lagged behind its counterparts on dry land for far too long, according to Andy Bowen, director of Woods Hole’s National Deep Submergence Facility. Bowen helped develop Jason Jr., the tethered robotic sub that first explored the Titanic in 1986, as well as Nereus, which explored the Mariana Trench in 2009.

“Undersea robotics has underachieved, in some ways, to demonstrate the potential we’re seeing in terrestrial applications, such as airborne drones or a robot that you can buy to sweep your floors,” Bowen said during the roundtable. “The undersea is difficult because there’s no GPS, there’s no wi-fi, there’s none of the things that make it possible to build a really diverse range of robotic tools for terrestrial applications.”

Most likely, exploration of the planet’s vast deep-sea trenches will require a combination of automated and manned vehicles to be successful. “So many people think we live in a post-exploration age—it’s all been seen, it’s all been mapped,” Cameron said. “How did we happen to get into the 21st century and miss a continent? The answer is obvious: It’s the hardest place to get to on the planet,” he noted, adding, “The aggregate area of these trenches is greater than the size of the United States, greater than the size of Australia, so it’s basically like a continent that’s been unexplored that exists right here on Earth.”

The world’s last unexplored continent—not a bad setting for a new science fiction movie, once Cameron returns from filming the further adventures of the Na'vi on their native Pandora, in the Alpha Centauri star system.