Liu Shiping waves as he walks out of submersible Jiaolong on May 23, 2017. China's manned submersible Jiaolong finished a dive in "Challenger Deep" in the Mariana Trench, the world's deepest known trench, on Tuesday. Xinhua News Agency journalist Liu Shiping descended inside the submersible along with scientists to 4,811 meters below the sea's surface. (Xinhua/Guo Songjiao)
