Which submersible was used by James Cameron to reach the Challenger Deep in 2012?
Answer
Deepsea Challenger
James Cameron used the Deepsea Challenger submersible to reach the Challenger Deep in 2012.
On March 26, 2012, Cameron piloted the one-person craft on a solo descent to the bottom of the Mariana Trench. The vehicle reached the seafloor after about two hours and 36 minutes and recorded a depth of approximately 10,908 meters. Cameron spent several hours exploring before beginning the ascent.
Deepsea Challenger was designed and built in Australia by the Acheron Project. It carried scientific sampling equipment, high-definition 3-D cameras, electric thrusters, and a thick pressure-resistant pilot sphere. The craft's vertical design and detachable ballast allowed it to sink rapidly and rise after releasing weight.
The other options belong to different milestones. Trieste carried Jacques Piccard and Don Walsh on the first crewed descent in 1960; Alvin is a famous research submersible that does not reach Challenger Deep; and Nereus was an uncrewed remotely operated vehicle that reached the site in 2009.