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The sub that took Hollywood director James Cameron to the deepest place in the ocean is being donated to science.

On the first anniversary of his 10.9km solo descent of the Mariana Trench, Mr Cameron told the BBC that he was giving the Deepsea Challenger to the Woods Hole Oceanographic Institution, US.

Initially, parts will be used as add-ons for other subs, but the entire system could dive again in the future.

Mr Cameron said he would like to return to the controls himself at some point.

Continue reading the main story “ Start Quote I'd like to go dive the sub again” End Quote James Cameron

"I'd like to go dive the sub again," he explained.

"There are a number of really, really interesting science targets out there. I would love to see the Deepsea Challenger dive in the Tonga Trench, the Kermadec Trench and the Sirena Deep (a 10.7km-deep part of the Mariana Trench)."

The director said that the ocean was a vast unexplored frontier, but that funding cuts were now jeopardising research.

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When Mr Cameron made his dive in 2012, he became the first person to reach the bottom of the Mariana Trench, which is in the western Pacific Ocean, for 50 years - and the only person to have ever made the descent alone.

The only previous manned dive to this deepest spot, called the Challenger Deep, was carried out by US Navy Lt Don Walsh and Swiss oceanographer Jacques Piccard. They took the plunge to the deepest point in the ocean in a bathyscaphe called Trieste in 1960.

It took Mr Cameron just two hours to reach the seafloor. While his bright green submersible moved through the water like a vertical torpedo, the director was squeezed into a tiny chamber that kept him safe from the colossal pressures that exist almost 11km down.

Continue reading the main story What lurks in the deep?

While at the bottom, he spent several hours exploring the seafloor. 3D cameras captured images for a National Geographic film that is being released later this year.

He told the BBC that donating the vessel to the Woods Hole Oceanographic Institution (WHOI) would give the sub "a second phase" of life after the dive. He said that funding was so scarce that plans to take the vehicle on a second series of dives had not been possible.

He explained: "I'd love to keep the Deepsea Challenger continuously operational. But I think that what I'm going for right now is what I call 'potentially operational'. The way to do that is to preserve the hardware 100%, which we'll do, but more importantly to preserve the culture of the engineering.

"My hope is with the sub's home now at Woods Hole, there will be a residential team in place - and they will have the knowledge of how to bring that sub back online."

New thinking

WHOI is one of the world's foremost research centres dedicated to ocean science. It already operates a a number of submersibles including the famous Alvin vehicle.

Initially, Woods Hole will use some of the components in Mr Cameron's sub to supplement its own vessels.

The lights and cameras from Deepsea Challenger will be installed on Nereus, an unmanned underwater vehicle that has also explored the Mariana Trench.

Many new species were seen on the sub's dives, says Mr Cameron

Dr Dave Gallo, director of special projects at WHOI, said the next stage would be to work out what other technology might be of use - and whether the submersible could be used again.

He added: "It is for one person, so you would have to have someone trained to do it - and we are looking very closely at every option."

The filmmaker said more money should be put into ocean science - and that it was essential to explore the biology and the chemistry of the deepsea.

The preliminary science results of the dive, which were released at the American Geophysical Union's Fall Meeting in San Francisco, suggest that the team had found many species that are new to science.

The presented results came from Mr Cameron's dive to the Challenger Deep in the Mariana Trench; an earlier dive to the New Britain Trench, off the coast of Papua New Guinea; and footage and samples taken from landers in the Sirena Deep.

The director told BBC News: "As an absolute minimum, (there were ) over 68 new species - most are bacteria, some are amphipods, and there is possibly a new sea cucumber... and that number may go way up.

"There were also some quite interesting new species of giant amphipods that were 7-8in long when amphipods are normally 0.5-1in in size."

But the explorer said he was surprised there were so little visible signs of life in the Mariana Trench.

"We expected there to be a big biomass in the sediment... but I expected more macrofauna, the things crawling around on the bottom. I had never seen a seafloor as devoid of macrofauna as the Challenger Deep.

"Is it because of the depth? Is it because it is so far from land and there is very little happening in the water column directly above it?"

Further exploration, he said, with the Deepsea Challenger and other robotic vessels would be the only way to find the answers.