Bathyscaphe Trieste
On 23 January 1960, she reached the ocean floor in the Challenger Deep (the deepest southern part of the Mariana Trench), carrying Jacques Piccard and Don Walsh. This was the first time a vessel, manned or unmanned, had reached the deepest known point of the Earth's oceans. The onboard systems indicated a depth of , although this was revised later to ; fairly recently, more accurate measurements have found Challenger Deep to be between and deep.
James Cameron
On March 7, 2012, Cameron took the "Deepsea Challenger" submersible to the bottom of the New Britain Trench in a five-mile-deep solo dive. On March 26, 2012, Cameron reached the Challenger Deep, the deepest part of the Mariana Trench. He spent more than three hours exploring the ocean floor before returning to the surface. Cameron is the first person to accomplish the trip solo. He was preceded by unmanned dives in 1995 and 2009 and by Jacques Piccard and Don Walsh, who were the first men to reach the bottom of the Mariana Trench aboard the Bathyscaphe Trieste in 1960. Cameron has made a three-dimensional film of his dive. During his dive to the Challenger Deep, the data he collected resulted in interesting new finds in the field of marine biology, including new species of sea cucumber, squid worm, and giant single-celled amoeba, which are exciting finds due to the harshness of the environment.