Development of Rockets

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The invention of the rocket is generally ascribed to the Chinese, who as early as A.D. 1000 stuffed gunpowder into sections of bamboo tubing to make military weapons of considerable effectiveness. The 13th-century English monk Roger Bacon introduced to Europe an improved form of gunpowder, which enabled rockets to become incendiary projectiles with a relatively long range. Rockets subsequently became a common if unreliable weapon. Major progress in design resulted from the work of William Congreve, an English artillery expert, who built a 20-lb (9-kg) rocket capable of traveling up to 2 mi (3 km). In the late 19th cent., the Austrian physicist Ernst Mach gave serious theoretical consideration to supersonic speeds and predicted the shock wave that causes sonic boom.

The astronautical use of rockets was cogently argued in the beginning of the 20th cent. by the Russian Konstantin E. Tsiolkovsky, who is sometimes called the "father of astronautics." He pointed out that a rocket can operate in a vacuum and suggested that multistage liquid-fuel rockets could escape the earth's gravitation. The greatest name in American rocketry is Robert H. Goddard, whose pamphlet A Method for Reaching Extreme Altitudes anticipated nearly all modern developments. Goddard launched the first liquid-fuel rocket in 1926 and demonstrated that rockets could be used to carry scientific apparatus into the upper atmosphere. His work found its most receptive audience in Germany. During World War II, a German team under Wernher von Braun developed the V-2 rocket, which was the first long-range guided missile. The V-2 had a range greater than 200 mi (322 km) and reached velocities of 3,500 mi (5,600 km) per hr.

After the war, rocket research in the United States and the Soviet Union intensified, leading to the development first of intercontinental ballistic missiles and then of modern spacecraft. Important U.S. rockets have included the Redstone, Jupiter, Atlas, Titan, Agena, Centaur, and Saturn carriers. Saturn V, the largest rocket ever assembled, developed 7.5 million lb (3.4 million kg) of thrust. A three-stage rocket, it stood 300 ft (91 m) high exclusive of payload and with the Apollo delivered a payload of 44 tons to the moon. Rockets presently being used to launch manned and unmanned missions into space include the U.S. Athena 1 and 2, Taurus, Titan 2 and 4B, Delta 2, 3, and 4, Atlas 2 ,3, and 5, and STS or space shuttle; the Chinese Long March 2C, 2E, and 2F; the Russian Soyuz and Proton K and M; the Japanese H-2A; the European Space Agency's Ariane 5 series; the Indian PSLV (Polar Satellite Launch Vehicle); the Israeli Shavit 2; the Brazilian VSV-30; and the multinational, private Sea Launch Zenit-3SL, which uses a converted oil platform located some 1,400 mi (2,250 km) southeast of Hawaii.

See also space science.

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