It's a real-life adventure that James Cameron has been planning for a long time — and one that may be only weeks away from coming true.


Sources are reporting that the 57-year-old is making final preparations to dive the Mariana Trench (a.k.a. the deepest part of the world's oceans) and descend nearly 36,000 feet in a custom-made submarine. Cameron first made public his intentions to make the trip back in September 2010. If successful, he would be the first person to do so since 1960, when a scientist and navy lieutenant descended five hours in the submersible "Trieste" to 35,797 feet.


"We are using lightweight but very strong carbon composite materials and other advanced technologies very different from the Trieste, which was a hollowed-out cannonball," he told The Sunday Times in 2010. "We believe we have solved most of the technological challenges to returning to the Mariana Trench. The real trick now is to make such vessels lighter, cheaper and more attractive to industry."


In an interview with the UK Telegraph, retired U.S. Navy Captain Don Walsh, one of the men who descended in the Trieste, says Cameron has a serious shot at taking on the Mariana soon. 


"Jim is a remarkable guy who's never trained as an engineer but has an intuitive grasp of engineering details that far surpass a lot of the professionals I've known," Walsh said. "He hasn't wasted a lot of time trumpeting to the world, 'We're going to do this.' He wants to make sure he's got it right and then he'll tell the world. He's a pretty high-profile person and he doesn't want to screw up royally."


Last July, at a National Geographic event honoring him with the prestigious "explorer-in-residence" title, Cameron said his goal was to reach the bottom in less than an hour "so that we can spend six or seven hours on the bottom doing science, taking images, taking core samples, discovering new species."


By comparison, it took the Trieste almost five hours to reach the sea floor. 


Should the "Avatar" director make the attempt soon, he would beat a competing effort underway by Richard Branson and his partner Chris Welsh. The pair, in partnership with the BBC, will dive to the deepest points of the world's five oceans. The journey will be documented using 3-D, Imax-quality images for a forthcoming cinema film named "Oceanic."


Rumors say Cameron, who will bring along his own high-tech cameras, may use some of the footage for the "Avatar" sequel, which will focus on the undersea alien world of Pandora. 


Michael d'Estries ( @michaeldestries ) covers science, technology, art, and the beautiful, unusual corners of our incredible world.

James Cameron poised to dive to ocean's deepest point
Rumors swirl that the film director and ocean explorer may dive 36,000 feet to the bottom of the Mariana Trench 'within weeks.'