High Quality Content by WIKIPEDIA articles! Don Walsh (born 2 November 1931) is an American oceanographer, explorer and marine policy specialist. He and Jacques Piccard were aboard the bathyscaphe Trieste when it made a record maximum descent into the Mariana Trench on 23 January 1960, the deepest point of the world`s ocean. The depth was measured at 35,813 feet (10,916 m), but later and more accurate measurements have measured it at 35,798 feet (10,911 m).