Project Nekton

Project Nekton was the codename for a series of very shallow test dives (three of them in Apra Harbor) and also deep-submergence operations in the Pacific Ocean near Guam that ended with the United States Navy-owned research bathyscaphe Trieste entering the Challenger Deep, the deepest surveyed point in the world's oceans.

The series of eight dives began with two harbor dives, then a Pacific ocean test dive at Guam, by the newly modified Trieste, which had been modified to dive far deeper than before. After two checkout dives, the first abyssal dive reached a record of 18,150 ft on November 15, 1959. The series included a record deep dive to near the bottom of the Nero deep in the Mariana Trench at 24,000 ft, and finally culminated with a trip to the bottom of the Challenger Deep at 35,797 feet, on January 23, 1960.

The project name was proposed by oceanographer Dr. Robert S. Dietz in early 1958, as plans to modify the Trieste bathyscaphe to go to the deepest part of the oceans were being contemplated. It is in reference to ocean life that actively swims (nekton) as opposed to the plankton organisms that only drift. The bathyscaphe Trieste to be used for Project Nekton was able to move independently, in contrast to tethered bathyspheres. The Trieste featured two electric motors, each with a propeller, of two horsepower each. These allowed it to move forward, backward and to turn horizontally. A maximum speed of 1 knot was attainable over a few miles distance.

Trieste departed San Diego on October 5, 1959 for Guam aboard the freighter SS Santa Mariana to participate in Project Nekton, a series of very deep dives near Guam, culminating in a descent to the Mariana Trench. It had been modified with a larger gasoline float, larger ballast tubs, and a newly designed heavy pressure sphere (made by Krupp in Germany), after having been purchased by the Office of Naval Research, which undertook the modification.

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