China's submersible Jiaolong starts testing ahead of Mariana Trench dive

Technicians prepare for theJiaolong, China's manned submersible, on its mother ship Xiangyanghong 09, May 22, 2017. The ship arrived at the Mariana area Monday and started testing temperature, salinity and depth for Tuesday's dive in the Mariana Trench, the first of the expedition's third stage. (Xinhua/Liu Shiping)