James Cameron mourns wrecked robot sub: ‘I feel like I’ve lost a friend’

James Cameron may be "king of the world," but Hollywood's most successful director is in mourning after it was reported that the deep-sea robot submarine Nereus was lost at sea.

"I feel like I've lost a friend," Cameron said on Tuesday. "Nereus was an amazing, groundbreaking robot and the only currently active vehicle in the world that could reach the extreme depths of the ocean trenches."

The Nereus suffered a catastrophic implosion from underwater pressure during an exploration mission in the Kermadec Trench, located off the coast of northern New Zealand. The submarine assisted Cameron on his history-making 2012 dive in the Mariana Trench.

The robotic vehicle was at a depth of 9,992 meters, about 6.2 miles, when it stopped responding. Operators of Nereus report that they lost contact with the vehicle about 7 hours into its planned 9-hour dive. After an attempted rescue, they spotted pieces of the vehicle floating on the water’s surface, confirming that it had imploded under extreme pressure while exploring the trench. Pressures at that depth are estimated to be 1,000 times greater than those at sea level.

Cameron donated the sub he used during the Mariana dive to the Woods Hole Oceanographic Institution (WHOI), which created the Nereus and assisted him during that expedition.

"Nereus helped us explore places we've never seen before and ask questions we never thought to ask," said WHOI scientist Tim Shank, who helped conceive the vessel. "It was a one-of-a-kind vehicle that even during its brief life, brought us amazing insights into the unexplored deep ocean, addressing some of the most fundamental scientific problems of our time about life on Earth."

The Nereus was the only robot submarine of its kind active in the world today. It was able to operate as a semiautonomous vehicle but could also be controlled directly by remote control. Thankfully, there are several other Nereus model submarines currently being built. So the kind of groundbreaking explorations it was undertaking should continue in the near future.

"I know what the Nereus team must be feeling...my heart goes out to them,” Cameron said. “They've not only lost a child, they've lost a great opportunity to explore one of the ocean's deep trenches ― the last great frontier for exploration on our planet."

Cameron, who is a member of the Oceans Elders collective, has been lobbying New Zealand to declare parts of the Kermadec region a marine reserve. The area is reported to be rich in mineral deposits, meaning it could be vulnerable to commercial exploration if not declared a protected area.

According to the group, the Kermadec is home to more than 400 species of fish and 11 percent of the world’s seabird population.

A 3-D documentary chronicling Cameron’s voyage to the bottom of the Mariana Trench will be released in theaters this August.

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