The Yaogan 30-01-01 to 30-01-03 (Remote Sensing Satellite-30-01-01 to 30-01-03) satellites, were launched by CZ-2C rocket from China's Xichang space center on 29 September 2017. The purpose is not confirmed, although the news reports hint towards a SIGINT mission, especially to detect ships by their radio emissions. They are also known as CX 5 by the manufacturer. The satellites are spaced by 120° in their orbit.
The Long March 2C is a family of expendable launch vehicles made and operated by China. It is a two stage launch vehicle with storable propellants, consisting of Nitrogen Tetroxide and Unsymmetrical Dimethylhydrazine.
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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