Manned submersible Jiaolong is put into the sea to conduct its first dive in Yap Trench, June 4, 2017. Jiaolong began diving at 8:43 a.m. local time on a rainy day, reaching a depth of 4,177 meters. There will be five dives for Jiaolong in the Yap Trench, and the last dive is planned for June 12. The dives will focus on research in deep-sea biotic communities and gene resources, according to scientists on the ship Xiangyanghong 09. (Xinhua/Liu Shiping)