Director James Cameron has said that he is close to diving 11km (seven miles) down to the deepest part of the ocean, the Mariana Trench in the western Pacific.

He has just successfully completed a test-dive 8km (five miles) down off the coast of Papua New Guinea.He now hopes to reach the world’s deepest point in his one-man submersible in the coming weeks.Only two people have been to the bottom of the Mariana Trench, back in 1960.

Cameron’s sub is called the Deepsea Challenge, and was built by an Australian team of engineers. It fits just one person, which will be the director himself.It is kitted out with cameras, including a small stereoscopic camera that can withstand the 1,000 atmospheres of pressure that are found 11km beneath the waves. Mr Cameron said that he plans to spend six hours exploring the bottom of the trench, and would be gathering footage for a 3D documentary based on the dive.He will also be collecting samples for the scientific community.

The expedition is backed by National Geographic and Rolex.The only people who have ever been to the Mariana Trench are Don Walsh, then a lieutenant in the US Navy, and Swiss oceanographer Jacques Piccard, who died in 2008. They made the dive in a vessel called the bathyscaphe Trieste on 23 January 1960.


   di Rebecca Morelle, BBC World  , 8 March 2012