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James Cameron Reaches Challenger Deep In The Mariana Trench
James Cameron is best known for his work as a film producer, director, writer and editor. He is also a world famous ocean explorer. He has explored the depths of the ocean, from his research at the site of the Titanic shipwreck, to reaching the deepest point in the ocean, Challenger Deep in the Mariana Trench.
Deep ocean exploration does not seem to get the same public attention and fame as space exploration. The extreme pressures of the depths of the ocean make any exploration a serious undertaking. The slightest mistake could prove fatal. Yet, there is still much that we have to learn about the oceans and what lives in the depths. The following is a look at James Cameron, the Mariana Trench and Challenger Deep.
Born in Canada in 1954, James Cameron moved to the United States when he was 17. The movie Star Wars sparked his interest in the film industry, igniting a lifelong passion. James Cameron worked for several years writing scripts and directing low budget movies. His first big break came when he wrote and directed The Terminator, which became a huge hit.
Cameron continued to work on major movies, including Aliens, The Abyss, Terminator 2, True Lies, Titanic and Avatar. The Abyss and Titanic sparked his interest in the ocean. A large portion of The Abyss was shot underwater in order to get a realistic atmosphere in a time before digital effects could create realistic environments. While filming for Titanic, Cameron personally made dives in a submersible to the wreckage of the Titanic.
On March 7, 2012, Cameron took the submersible, Deepsea Challenger on a file mile deep solo dive to the bottom of the New Britain Trench. This was a test dive to prove the capabilities of the Deepsea Challenger. It also tested the communication equipment, mechanics and video equipment for it's journey to Challenger Deep.
The mariana Trench is located along the western side of the Pacific Ocean. It is east of and named for the Mariana Islands. The trench is about 1,580 miles long, but averages only 43 miles wide. The deepest point of the trench, named Challenger Deep was most recently measured at about 36,000 feet deep. The pressure at that depth is over 1,000 times the pressure of air at sea level.
The Mariana Trench formed as a boundary between the Pacific Tectonic Plate and the Mariana Tectonic Plate. At one time, the location between the tectonic plates and the pressure made the Mariana Trench appear to be a perfect dump site for nuclear waste. The theory was that the movement of the tectonic plates would eventually cause the nuclear waste to be pushed into the core of the earth. Fortunately the site was never used for dumping. Frequent earthquakes brought up concerns that the nuclear material could be spread to other parts of the ocean. And, despite the crushing pressure at depth, a shrimp and a fish, possibly a flounder, were observed near the bottom of the trench, proving that even the greatest depths of the ocean are home to living creatures
In the 1870s, the Mariana Trench was first measured using sounding equipment that was state of the art at the time. The measured the depth of the trench was 26,850. At the time, it was called Challenger Tief (German for Challenger Deep). Over the years there were many attempts to figure out the exact depth. In 2011, it was measured at 36,070 feet, which is believed to be the most accurate measurement to date.
Exploring Challenger Deep
The crushing depth of Challenger Deep has limited the number of visitors that have seen the icy darkness. Only two manned vessels and two Remotely Operated Vessels (ROVs) have been sent to explore the depths.
On January 23, 1960, Jacques Piccard and Don Walsh became the first two people to see the bottom of Challenger Deep. They completed their journey in the Trieste, a type of submarine called a bathyscaphe (see picture at right). It consisted of a round pressure-safe compartment below a large container of gasoline. They used gasoline for buoyancy because it is lighter than water, but will not compress the way some lighter materials would. They also used lead weight to get them to the bottom.
The Trieste took nearly five hours to reach the bottom. They adjusted their rate of descent by releasing either lead or gasoline. Once on the bottom, the Trieste was only able to remain for 20 minutes. They did not bring any photographic equipment along, so the only information about the bottom came from the descriptions that Piccard and Walsh provided. When they were ready to ascend they dumped the remaining lead ballast. It took just over three hours for them to reach the surface.
An ROV tether is a cable that serves as a way to transfer information between an ROV and the operator. It sends control commands to the ROV to allow the operator to maneuver the ROV around the ocean floor. It also allows the ROV to send information back to the ship, such as video and the temperature on the ocean floor.
After 35 years, Challenger Deep saw it's next visitor on March 24, 1995. On that day, the Japanese ROV Kaiko became the first ROV to reach the deepest part of the ocean. Before that day, no ROV had ever reached depths anywhere near those of the Mariana Trench. The Kaiko collected soil samples before returning to the surface. Those soil samples proved that there were living organisms, despite the crushing pressure. The Kaiko made additional dives in 1996 and 1998.
Eleven years later, the United States sent a new ROV to Challenger Deep. The Nereus is a new bread of ROV. Unlike previous ROVs, including the Kaiko, the Nereus does not require a tether to operate. The lack of a tether makes the Nereus more maneuverable than previous generations of ROVs. The Nereus spent 10 hours at the bottom, providing live video and data to its operators at the surface.
The first solo trip to the bottom of Challenger Deep was completed by James Cameron in the Deepsea Challenger. The Deepsea Challenger is made primarily out of a special hi-tech foam that gives the submersible buoyancy, but is resistant to the crushing pressure of the water at those depths. The foam is so strong that the thrusters and batteries of the submersible were mounted directly into the foam, with no need for a steel superstructure to support it.
The Challenger can only fit one pilot. The steel hull of the pilot compartment was pressure tested at Pennsylvania State University prior to testing at depth. James Cameron then made progressive dives from just under the surface to 3,300 feet, then to just over 12,000 feet and 26,972 feet to test the Challenger and make sure that it was ready to dive the deepest part of the ocean.
On March 26, 2012, James Cameron took 2 hours and 37 minutes to reach the bottom of Challenger Deep. He was able to spend a little over 3 hours at the bottom. Despite some minor technical difficulties limiting the amount of time that Cameron could spend at the bottom, he made it back to the surface safely and with high definition video footage of the bottom of the ocean.
Below is a drawing of the main components of the Deepsea Challenger: