Deepest-dive anniversary

25 January 2010

Fifty years ago, on January 23, 1960, Jacques Piccard and Lt. Don Walsh descended in the bathyscaphe Trieste to the bottom of the Challenger Deep in the Marianas Trench, approximately 35,800 feet, setting a record for manned diving that still holds today.

Launched in 1953, the bathyscaphe (“deep boat”) Trieste was designed and built by Swiss physicist Professor Auguste Piccard and his son Jacques. It was purchased by the US Navy in 1958 and modified for a program of deep-sea dives off Guam. On the record-setting descent to the deepest spot in the oceans, Piccard and Walsh were inside the submersible for more than eight hours—four hours and 45 minutes down and three hours and 17 minutes returning to the surface. They spent 20 minutes on the sea floor, observing fish, shrimp and other marine life.

A bulky, cumbersome vessel, Trieste was roughly 60 feet long and 11.5 feet abeam. The design echoed the Piccards’ ground-breaking design of balloons for scientific study. A swollen superstructure housed the propulsion and buoyancy-control systems while passengers rode in a pressure sphere “gondola” beneath, crowded with equipment.