XI QIXIN (original author), a retired journalist of the General Armament Department (GAD) of the People's Liberation Army, was once head of the GAD Branch of the Xinhua News Agency, holding the rank of senior colonel. He has worked for the publicity of national defense science and technology for more than three decades and has participated in nearly 100 major national defense research and experiment projects, such as tests of missiles, satellites and nuclear weapons, and manned spaceflights. YANG LIANG (adapter), deputy director of the Exhibition Department of Qian Xuesen Library & Museum.