The deepest deep-submergence vehicle (DSV) to date is "Trieste". On 5 October 1959, "Trieste" departed San Diego for Guam aboard the freighter "Santa Maria" to participate in "Project Nekton", a series of very deep dives in the Mariana Trench. On 23 January 1960, "Trieste" reached the ocean floor in the Challenger Deep (the deepest southern part of the Mariana Trench), carrying Jacques Piccard (son of Auguste) and Lieutenant Don Walsh, USN. This was the first time a vessel, manned or unmanned, had reached the deepest point in the Earth's oceans. The onboard systems indicated a depth of , although this was later revised to and more accurate measurements made in 1995 have found the Challenger Deep slightly shallower, at .