Shijian 20 is an experimental geostationary communications satellite. This is also a return-to-flight launch for Long March 5 after a July 2017 failure.
Long March 5 is a Chinese heavy lift launch system developed by China Academy of Launch Vehicle Technology (CALT). CZ-5 is the first Chinese vehicle designed from the ground up to focus on non-hypergolic liquid rocket propellants. Currently, two CZ-5 vehicle configurations are planned, with maximum payload capacities of ~25,000 kilograms (55,000 lb) to LEO and ~14,000 kilograms (31,000 lb) to GTO. The Long March 5 roughly matches the capabilities of American EELV heavy-class vehicles such as the Delta IV Heavy.
The China Aerospace Science and Technology Corporation (CASC) is the main contractor for the Chinese space program. It is state-owned and has a number of subordinate entities which design, develop and manufacture a range of spacecraft, launch vehicles, strategic and tactical missile systems, and ground equipment. It was officially established in July 1999 as part of a Chinese government reform drive, having previously been one part of the former China Aerospace Corporation. Various incarnations of the program date back to 1956.INFO WIKI