Jiaolong, China’s manned submersible, arrived at the Mariana Trench yesterday and began testing temperature, salinity and depth for a dive today, the first of the expedition’s third stage. Ten dives are planned, with the first reaching a depth of 4,800 meters. Chief crew member Tang Jialing said the dive will take place at the steeper northern slope of the Mariana’s “Challenger Deep.” — Xinhua