Qian Xuesen
After returning to China, Sun served in the Fifth Research Institute of the Ministry of National Defense, conducting missile research. In 1967, he was appointed by Qian Xuesen to restructure the staff for satellite research. In addition to being in charge of the general design project for China's first satellite, he also worked as the technical superintendent and general designer for both China's first remote sensing satellite and recoverable satellite. He was also the chief designer of a second generation of special application satellites, such as communication, meteorological, and earth resource detecting satellites, as well as the Beidou-2 navigation system.