Chinese marine research vessel Haiyang 6 (Ocean 6) returns to Guangzhou, capital of south China's Guangdong Province, Oct. 23, 2019. Chinese marine research vessel Haiyang 6 (Ocean 6) has completed its deep-sea exploration mission in the Western Pacific ocean after 122 days and 35,000 km at sea. The vessel returned to Guangzhou on Wednesday. [Photo/Xinhua]