All modern liquid rockets can be traced to the V-2, the first real ballistic missile. An unmanned missile guided by a gyroscopic system, it burned a fuel containing alcohol and liquid oxygen. The V-2 had a range of over 320 kilometers, and it could transport an explosive warhead that weighed a ton. (U.S. Army White Sands Missile Range) |
People have been building rockets in various forms for centuries. In 1232, the Chinese army shot "fire arrows"—solid rockets propelled by a gunpowder mixture of charcoal, sulfur, and potassium nitrate (saltpeter)—at invading Mongols in the Battle of Kai-Fung-Fu. Besides military weapons, other applications for rockets over the years have included fireworks, lifesaving devices (as early as 1882), whaling operations (as early as 1865), and signal and illumination devices.
The basics of rocketry have not changed. Ignited fuel burns in a combustion chamber, and the resulting gases are forcefully expelled through a nozzle, propelling the rocket in the opposite direction. Until the first quarter of the 20th century, all rockets were developed using solid propellant. Today's space systems employ both solid-rocket motors and liquid-rocket engines to deliver payloads into orbit.
Original rocket technology did not progress much until the early 19th century, when Colonel William Congreve of England developed effective bomb-carrying solid rockets. Long sticks trailed from his rockets to provide stability. Soldiers put Congreve's rockets to use during the British bombardment of Baltimore in 1814, at Waterloo in the war with Napoleon in 1815, and in the Opium War with China in 1842. (The bombardment of Baltimore and "the rockets' red glare" inspired Francis Scott Key's famous poem "The Defense of Fort McHenry," adopted later as the U.S. national anthem, "The Star-Spangled Banner.") Congreve's fellow Englishman, William Hale, developed a more accurate stickless, spin-stabilized rocket in 1844.
In the early 20th century, Wilhelm Teodore Unge of Sweden improved the mechanical strength and workability of solid propellant and developed launcher-rotated rockets that could travel eight kilometers with great accuracy. Y. P. G. Le Prieur of France invented stick-guided solid rockets for firing through steel tubes mounted on the wing strut of a biplane, which were used successfully in World War I against German observation balloons. These constituted an early version of air-launched missiles.
Konstantin Eduardovitch Tsiolkovsky of Russia first introduced the idea of using rockets for space exploration in 1903. Subsequently the idea was proposed by Robert Hutchings Goddard of the United States in 1919, Hermann Oberth of Germany in 1923, and Robert Esnault-Pelterie of France in 1928.
In 1926, Goddard built a successful rocket using liquid propellant (gasoline as fuel and liquid oxygen as oxidizer). Germans used his 1939 design of a liquid rocket to build and test the first full-scale ballistic missile, Vergeltungswaffe-2 (V-2, "Weapon of Retaliation-2"), in 1942. All modern liquid rockets can be traced to the V-2. With a mixture of ethyl alcohol as fuel and liquid oxygen as oxidizer, it could travel 320 kilometers. The V-2 carried warheads from the European continent to England in the "Siege of London" during World War II.
At the end of the war, Russia captured V-2 manufacturing plants, including many German rocket scientists and engineers, and set up its own ballistic missiles and space launch programs under the leadership of Sergei P. Korolev. Meanwhile, Wernher von Braun, the leader of the German V-2 program, and his coworkers continued their research on ballistic missiles and space launch vehicle development in the United States. During the 46 years of the Cold War between the United States and the USSR (September 2, 1945, through December 26, 1991), ballistic-missile buildup and the space race fostered the continued growth of rocket science.