Officially described as "Satellite-Internet Technology Demonstration Satellite(s)" built by Chinese Academy of Sciences. Probable 3 (?) test satellites for the Chinese state-owned LEO communication satellite constellation SatNet.
The Long March 2D, also known as the Chang Zheng 2D, CZ-2D and LM-2D, is a Chinese orbital carrier rocket. It is a 2-stage carrier rocket mainly used for launching LEO and SSO satellites. The YZ-3 variant includes a YZ-3 upper stage able to push satellites into higher orbits.
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.
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