The author of Avatar, James Cameron, is assembling a team to dive to the bottom of the deepest sea. He is planning to shoot footage for a sequel to Avatar. The movie is set in the turbulent waters of Pandora, an alien moon, and it’s expected to hit the circuit in 2014. Cameron has commissioned Australian engineers to build a deep sea submersible to reach the bottom of the Marianas Trench.
“We are building a vehicle to do the dive. It’s about half-completed in Australia,” said Cameron.
Camerons destination is an area known as “Challenger Deep”. At 10 916 meters (35 813 feet) below sea level, this is the deepest surveyed point on earth. It lies in the hadopelagic or Hadal zone so named from the greek word ” Hades” for the “underworld.”
This deepest part of the ocean floor has been visited only once before, in January of 1960, and never since. A US Navy mission in the Swiss-designed submersible, the Trieste, was manned by Don Walsh and Jacques Piccard, son of Auguste Piccard the designer of the Trieste. They volunteered at a time when the space race to the moon was in the public’s imagination. The Chief of Naval Operations ordered them not to discuss their mission with anyone until it was completed. That’s the way things were done then.
Although the Trieste looks like a submarine, it is not. The design principal is that of a sphere, containing the divers, attached to a huge buoyancy tank. The tank was filled with 126 000 liters (33 350 gallons) of gasoline. Gasoline was chosen for it’s buoyancy and particularly because it is relatively incompressible even at the extreme 200 000 ton pressure found at the bottom of the deep. The 13 ton sphere measures 2 meters (6 feet, 6 inches) in diameter with 127 mm (5 inch) thick walls, creating fairly cramped conditions for two people. Entry was from the top “sail” above the tank down a tube passing through the buoyancy tank into the sphere. The sphere provided completely independent life support, with a closed-circuit re-breather system. The beauty of the bathyscaphe design was that it allowed for an independent and free diving vehicle, rather than the earlier more cumbersome bathysphere designs comprising a sphere that was lowered down and raised again by cable from a ship.
The dive took just less than five hours. At 9,000 meters a loud crack sounded and the ship shuddered as an outer plexiglass pane cracked, giving Walsh and Piccard some tense moments. Fortunately the craft held intact and they decided to continue their descent. As the vehicle touched down it kicked up a white cloud of fine silt that obscured the view. The milky cloud was a diatomaceous ooze, the silica skeletons of small sea creatures. Shortly before reaching the bottom Piccard had seen a flat fish, resembling a sole, on the sea floor. They also observed some shrimp. Walsh and Piccard spent only 20 minutes on the ocean floor but their mission set a record for the deepest descent ever. To initiate their return to the surface the argonauts released a portion of the nine tons of iron pellet balast held in two hoppers. The return trip was a much speedier three hours and 17 minutes.
Marine biologists once doubted that flatfish could survive at such extreme depths. Modern robotic “landers” have filmed hordes of weird white snail-fish-like, foot-long tadpoles with suckers on their bellies in the hadopelagic zone. For scientists the intriguing question now arises: how did the worlds deepest oceans, so isolated from one another, come to host so many subtly different and peculiar creatures. The intense pressure at these depths has evolved some strange life forms with a more robust physiology at the molecular level, perhaps the perfect canvas for a movie director like James Cameron.