'Titanic' Director Makes First Solo Dive to Earth's Deepest Point

March 25 (Reuters) - "Titanic" film director James Cameron has completed the world's first solo dive to the deepest known point on Earth, reaching the bottom of the Pacific Ocean's Mariana Trench southwest of Guam in a specially designed submarine.

The filmmaker arrived at the site known as "Challenger Deep" shortly before 8 a.m. local time Monday (6 p.m. EDT on Sunday), reaching a depth of 35,756 feet (10,898 meters), or roughly 7 miles beneath the ocean's surface, said the National Geographic Society, which is overseeing the expedition.

Cameron's first words to the surface upon reaching the bottom were, "All systems OK," National Geographic said on its website.

"Hitting bottom never felt so good. Can't wait to share what I'm seeing w/ you," the filmmaker said in a separate Twitter message posted just after he touched down.

The low-point of the Mariana Trench, a great valley below the Pacific, has been reached by humans just once before, in 1960 when U.S. Navy Lieutenant Don Walsh and Swiss oceanographer Jacques Piccard spent 20 minutes there in the bathyscaphe Trieste.

Cameron, the first to make a solo dive to the spot, planned to spend six hours there collecting research samples for marine biology and geology.

The expedition is a joint project by Cameron, National Geographic and watchmaker Rolex that has been dubbed "Deepsea Challenge" and is designed to expand understanding of a little-known corner of the Earth.

The single-man vehicle piloted by Cameron, the Deepsea Challenger, stands 24 feet (7 meters) tall and was designed to descend upright and rotating at a speed of about 500 feet (150 meters) per minute.

The submersible represents breakthroughs in materials science, structural engineering and imaging through an ultra-small, full-ocean depth-rated stereoscopic camera.

While he is perhaps better known as director of such films as "Titanic," "Avatar" and "Aliens," Cameron is no stranger to underwater exploration. For "Titanic," he took 12 dives to the famed shipwreck in the North Atlantic, leading him to develop deep-sea film and exploration technology.

Since then he has led six expeditions, authored a forensic study of the German battleship Bismarck wreck site and conducted extensive 3-D imaging of deep hydrothermal vents along the Mid-Atlantic Ridge, the East Pacific Rise and the Sea of Cortez. (Reporting and writing by Steve Gorman; Editing by David Bailey and Stacey Joyce)