23 January 1960. Challenger Deep.
Lieutenant Don Walsh of the U.S. Navy and Swiss engineer Jacques Piccard descended in the bathyscaphe Trieste to Challenger Deep in the Mariana Trench, the deepest point in any of the world’s oceans. The dive reached a depth measured at 10,916 meters. Bottom time was 20 minutes, cut short after an outer viewport cracked during the descent.
Walsh and Piccard were the only two humans to reach Challenger Deep until 2012, when James Cameron made a solo descent in the Deepsea Challenger. The depth was reached again in 2019 with the Limiting Factor expeditions.
The watch on his wrist: an Aquastar Model 60.
Walsh wore an Aquastar Model 60 on the Trieste descent, a fact he personally verified to Aquastar in his later years, sending the brand a photograph of the watch from his collection.
The Model 60, Aquastar’s cushion-case dive watch, was the first Aquastar reference in production. That a U.S. Navy lieutenant chose it for the deepest dive ever attempted by a crewed vessel is the earliest documented connection between the brand and the limits of human ocean exploration.
A long career after the deep.
Walsh continued in the U.S. Navy after the Trieste dive, retiring as a Captain. He earned a PhD in physical oceanography from Texas A&M University. He served on the U.S. delegation to the Law of the Sea negotiations and held the presidency of the Marine Technology Society and the Explorers Club, among other roles in oceanographic policy and exploration.
He died on 12 November 2023 at the age of 92.
