On April 20, 2017 at 11:40 UTC the Chang Zheng-7 (Long March-7) rocket-carrier was launched from Wenchang Satellite Launch Center (WSLC), located in Wenchang on Hainan Island off China’s southern coastline.

The rocket orbited the “Tianzhou-1” unmanned supply spacecraft. The “Tianzhou-1” (Chinese: 天舟一号) is the test mission of the Tianzhou-class unmanned cargo spacecraft. It is developed as part of the manned space program of China. Tianzhou means "heavenly vessel" in Chinese. The spacecraft is to dock with the Chinese “Tiangong-2” space station to conduct several months of robotic demonstrations, practicing for the assembly and maintenance of a future permanently-staffed orbital research complex. “Tianzhou-1” is the heaviest Chinese spacecraft ever launched, weighing around 13 metric tons with a full load of propellant. Designed to accommodate up to 6500 kilograms of payloads, the “Tianzhou” spacecraft is similar in purpose to cargo freighters that fly to the International Space Station, such as the Russian “Progress” supply spacecraft and the commercial “Cygnus” and “Dragon” space vehicles built by Orbital ATK and SpaceX.