Strategic Defense Initiative (SDI), U.S. government program responsible for research and development of a space-based system to defend the nation from attack by strategic ballistic missiles (s...

Korolev, Sergei Pavlovich, 1907–66, Soviet rocket designer. His role as chief designer of the Soviet space program was revealed only after his death. After he successfully launched two interco...

Vandenberg Air Force Base, U.S. military installation, 3,456 acres (1,399 hectares), SW Calif., near Lompoc; chief Pacific coast launch site for military satellites. Commercial satellites are ...

Guided missile, self-propelled, unmanned space or air vehicle carrying an explosive warhead. Its path can be adjusted during flight, either by automatic self-contained controls or remote human...

Baikonur or Baykonur Cosmodrome, formerly secret aerospace launch complex, Qyzylorda prov., S central Kazakhstan, near Leninsk (now Baikonur) but c.200 mi (320 km) SW of the mining town of Bai...

Mach, Ernst, 1838–1916, Austrian physicist and philosopher, b. Moravia. He taught (1864–67) mathematics at Graz and later, until his retirement in 1901, was professor of physics at Prague and ...

Strategic Air Command (SAC), former command of the U.S. air force (see Air Force, United States Department of the) charged with organizing, training, equipping, administering, and preparing st...

Cuban Missile Crisis, 1962, major cold war confrontation between the United States and the Soviet Union. After the Bay of Pigs Invasion, the USSR increased its support of Fidel Castro's Cuban ...

Reconnaissance satellite, artificial satellite launched by a country to provide intelligence information on the military activities of foreign countries. There are four major types. Early-warn...

Disarmament, nuclear, the reduction and limitation of the various nuclear weapons in the military forces of the world's nations. The atomic bombs dropped (1945) on Japan by the United States i...