Konstantin Eduardovich Tsiolkovsky

views updated May 21 2018

Konstantin Eduardovich Tsiolkovsky

The Russian scientist Konstantin Eduardovich Tsiolkovsky (1857-1935) formulated the mathematical fundamentals of modern astronautics. He showed that space travel was possible only by means of rocket propulsion.

Konstantin Tsiolkovsky was born on Sept. 17, 1857, in the village of Izhevskoye, Ryazan Province. His father was successively a forester, teacher, and minor government official. When he was ten Konstantin contracted scarlet fever, which left him with permanently impaired hearing. He became passionately interested in science and mathematics. At the age of 16 he went to Moscow. He made an ear trumpet himself and attended lectures and studied in libraries. Regular attendance at the university was out of the question because of the costs involved and his deafness.

Hardships in Moscow

Tsiolkovsky seriously began considering the problems of space exploration. While still not completely schooled in physics, he developed a machine that he thought might someday reach outer space by means of centrifugal force. It was a box in which there were two steel rods with balls on their ends. When the rods were set in motion, their vibrations (in Tsiolkovsky's theory) would produce an upward movement because of centrifugal force, but they did not.

In 1876 Tsiolkovsky went home, which was now in Viatka in the Urals. There he became a private tutor in physics and mathematics. He converted a room into a workshop in which he built machines. In 1878, the family returned to Ryazan, and Tsiolkovsky received a certificate as a "people's school teacher, " the lowest classification in the educational system of the day. He took a job as a teacher of arithmetic, geometry, and physics at the district school in Borovsk near Moscow.

In 1880 Tsiolkovsky wrote his first serious scientific paper, "The Graphical Depiction of Sensations." It was an attempt to reduce to mathematical models the experience of human senses. The following year he submitted the paper "The Theory of Gas" to the Physical and Chemical Society in St. Petersburg. Later he submitted another paper, "The Theoretical Mechanics of a Living Organism, " for which he was elected to the society. In 1883 he published a purely qualitative study entitled "Free Space, " in which he examined the motion of a body not under the influence of a gravitational field or some medium that offered resistance to its movement; the paper contained a drawing of a rocket-powered space ship.

After 1884 three areas of science occupied Tsiolkovsky. He began to concentrate on aeronautics: a streamlined airplane, an aerostation, an all-metal dirigible, and space travel. In 1886 he published an essay on the theory of the dirigible and was invited to Moscow to lecture on his ideas. His concept of the dirigible was highly imaginative and theoretically feasible, but it posed serious problems for the engineering of the day. He proposed all-metal airships with a variable volume to preserve constant buoyancy at different temperatures and altitudes. A corrugated metal envelope with an internal system of pulleys was to vary the volume as the temperature or altitude changed. The lifting gas (hydrogen) was to be heated by passing the exhaust gases from the engines through the envelope before they were discharged to the atmosphere. His plans submitted to the Russian Technical Society's Aeronautical Department in 1891 brought a reply that "inasmuch as the project cannot have any considerable practical importance, the society did not find it possible to comply with your request for a grant to construct a model." The tone of this letter was to become familiar to him over the remainder of his life. The only funds he ever received from any outside source came from the Academy of Sciences and amounted to only 470 rubles ($235).

In 1892 Tsiolkovsky became a high school teacher in Kaluga. In 1894 he published the article "The Airplane or Bird-like Flying Machine."

First Wind Tunnel

In 1897 Tsiolkovsky built the first wind tunnel in Russia. In it, he tested a number of different airfoils to determine their lift coefficients. The results of these pioneering experiments in aeronautical engineering were published the following year, and the Academy of Sciences in St. Petersburg granted him 470 rubles to expand and exploit his research in this field. He built a bigger machine, but even as he was wrapped up with his wind tunnel, he found time to think about rockets and space travel.

In 1897 Tsiolkovsky derived the relationship of the exhaust velocity of a rocket and its mass ratio to its instantaneous velocity. Known today as the basic rocket equation, it is expressed as V = c In (W i /Wf ), in which V is the final velocity, c is the exhaust velocity of propellant particles expelled through the nozzle, Wi is the initial weight of the rocket, and W f is the final, or burnt-out, weight of the rocket. Of course, it does not consider the retarding forces of gravity and drag, which Tsiolkovsky knew affected the rocket and later took into account in refining his equation. What his equation proved was that the velocity of a rocket in space depends on the velocity of its exhaust and the ratio of the weight of the rocket at lift-off and at burn-out. This realization permitted him to conceive of many ways of increasing the exhaust velocity and of decreasing the mass fraction.

Even more important from the astronautical viewpoint, Tsiolkovsky demonstrated that the answer to space travel lay in building what he called "step, or train, " rockets. Today this concept is known as "staging." He saw, from his mathematical investigations, that a rocket could attain greater velocities if it could grow continuously lighter. Thus, he suggested that rockets could be clustered in the tandem, or parallel, configuration. As stages burned out, they dropped away, and upper stages gained in velocity as a result—as his rocket equation proved.

Contributions to Astronautics

In 1903 Tsiolkovsky finished a paper that was to become his famous article "Investigation of Outer Space by Reaction Devices." It did not appear in print until 1911 and 1912, when it was published serially in the Aeronautical Courier (Vestnik Vozdukhoplavaniva). This work represents his major contribution to astronautical engineering. He reiterated his rocket equation and modified it to include the forces of gravity and drag. He examined the energies involved in a vertical and horizontal launching, and he considered the best overall shape for a rocket. Also, he demonstrated that solid propellants lacked the energy needed for interplanetary travel. In considering various liquid propellants, he arrived at liquid hydrogen and liquid oxygen as the most practical. He also mentioned the theoretical advantage of ozone instead of diatomic oxygen. The concept of the regeneratively cooled engine is also found in this work.

During the late 1920s and the early 1930s, Tsiolkovsky's interests shifted to the airplane, especially the rocket-propelled model. Of the articles appearing in this period, typical are "The New Airplane" (1929), "The Reaction Airplane" (1930), and "Rocketplane" (1930). After Tsiolkovsky retired from teaching, he continued to write on space and aeronautics.

In 1934, as he knew he was dying of cancer, Tsiolkovsky became worried about the future welfare of his family. On Sept. 13, 1935, he wrote a letter to the Central Committee of the Communist Party bequeathing all of his writings "to the Bolshevik Party and the Soviet Government." In so doing, he hoped he might obtain a pension for his family. He died on September 19.

For several years Tsiolkovsky's books and manuscripts were stored in the central offices of Aeroflot and then given to various museums. His home in Kaluga was made into a museum, and some of the material was returned to it. During World War II the museum suffered depredation by the invading Germans, but the staff managed to save much of the material. Following the orbiting of Sputnik 1, the world's first satellite, the Tsiolkovsky Museum became a very popular attraction in the Soviet Union.

Further Reading

There is no readily accessible biography of Tsiolkovsky in English. A. Kosmodemyansky, Konstantin Tsiolkovsky: His Life and Work (Moscow, 1956), is not well known in the United States and suffers from a heavy burden of political propaganda. Much more objective is V. N. Sokolsky, K. E. Tsiolkovsky: Selected Works (Moscow, 1968); it is a compendium of Tsiolkovsky's works with a short biography appended, but it is also not widely available in the United States. Perhaps the best sources in English, which draw heavily on the above-cited references, are Willy Ley, Rockets, Missiles, and Men in Space (1952; rev. ed. 1968); Beryl Williams and Samuel Epstein, The Rocket Pioneers on the Road to Space (1958); and Albert Parry, Russia's Rockets and Missiles (1960). □

Tsiolkovsky, Konstantin Eduardovich

views updated May 21 2018


(b. Izhevsk, Ryazan guberniya, Russia, 17 September 1857; d. Kaluga, U.S.S.R., 19 September 1935)

mechanics, aeronautics, astronautics.

Tsiolkovsky was the son of a forester. At the age of nine he became almost completely deaf following a serious illness. Unable to continue in school, he was obliged to study on his own, using his father’s library. From the age of thirteen Tsiolkovsky began systematically to study the natural sciences. It was at this time that his inclination for invention became apparent.

In 1873, his father sent him to Moscow to continue his self-education. Studying on his own. Tsiolkovsky completed the entire secondary school course and a considerable part of the univeristy course.

After having passed the teaching examination in 1879–without attending lectures–Tsiolkovsky was appointed in 1880 to the Borovsk district school, sixty miles southwest of Moscow, where he taught arithmetic and geometry. He devoted most of his free time to scientific investigations.

In the mid–1880’s, Tsiolkovsky began research in aerostatics. He worked out a project for an allmetal dirigible with a corrugated metal shell, the volume of which could be varied in flight. Tsiolkovsky further developed his dirigible theory in “Aerostat metallichesky upravlyaemy” (“A Controlled Metal Dirigible,” 1892).

In “K voprosu o letanii posredstvom krylev” (“On the Question of Winged Flight”), completed in 1890. Tsiolkovsky investigated the magnitude of forces acting upon a moving disk. In this work he made the first attempt to evaluate quantitatively the influence of the length of the disk on the magnitude of the aerodynamic forces. In 1891, part of the work was printed by the Society of Friends of Natural Science under the title “Davlenie zhidkosti na ravnomerno dvizhushchuyusya v ney ploskost” (“The Pressure of a Fluid on a Plane Moving Uniformly Through It”). It was Tsiolkovsky’s first published work.

In 1892 Tsiolkovsky moved to Kaluga, where he continued to teach without interrupting his scientific research. In 1894 his work “Aeroplan ili ptitsepodobnaya (aviatsionnaya) letatelnaya mashina” (“The Aeroplane, or A Flying Birdlike Machine [Aircraft] “) was published in Nauka i zhizn. In this work he proposed a plan for a plane having a metal frame (similar to contemporary aircraft)–a monoplane with a streamlined fuselage, freely supported wings, a thick profile with a rounded forward edge, a wheeled undercarriage, and an internal combustion engine. He also suggested using twin screw propellers rotating in opposite directions. He expounded the idea of using the gyroscope in aircraft as a simple automatic pilot.

While working on these projects Tsiolkovsky came to grips with the unavoidable necessity of obtaining precise data on the resistance of a medium. A series of experiments under natural conditions led him to test his models in an artificial airstream. In 1897 he constructed a wind tunnel, the first in Russia to be used in aviation.

Of greater significance are Tsiolkovsky’s works on outer space. He became interested in questions of interplanetary travel at the age of sixteen. In “Svobodnoe prostranstvo” (“Free Space,” 1883), he examined phenomena that occur in a medium in which the forces of gravity–for all practical purposes–are not active. This paper included the first formulation of the possibility of applying the principle of reactive motion for flight in a vacuum, which led to a simple plan for a spaceship. Tsiolkovsky also considered several questions concerning the necessary conditions of life for plants and animals in space.

In 1896 Tsiolkovsky began to explore the possibility of interplanetary travel by means of rockets. In 1897 he formulated his now widely known formula establishing the analytical dependence between the velocity of a rocket at a given moment, the velocity of the expulsion of gas particles from the nozzle of the engine, the mass of the rocket, and the mass of the expended explosive material.

In “Issledovanie mirovykh prostranstv reaktivnymi priborami” (“A Study of Atmospheric Space Using Reactive Devices,” 1903), Tsiolkovsky set forth his theory of the motion of rockets, established the possibility of space travel by means of rockets, and adduced the fundamental flight formulas.

Tsiolkovsky contributed to the recently established mechanics of bodies of changing mass. He evolved a theory of rocket flight taking into account the change of mass while in motion; he suggested the concept of gas-driven rudders for guiding a rocket in a vacuum; and he determined the coefficient of a rocket’s practical operation.

From 1903 to 1917 Tsiolkovsky offered several plans for constructing rocket ships. He considered such questions as guiding a rocket in a vacuum, the use of a fuel component to cool the combustion chamber walls, and the application of refractory elements.

Tsiolkovsky’s advanced ideas did not find acceptance. He was met with indifference and disbelief, and many considered this autodidact to be a rootless dreamer. Having received neither material nor moral support, Tsiolkovsky was left to his own resources. “It has been difficult for me,” he wrote with bitterness, “to work alone for many years under unfavorable conditions and not even to see the possibility for hope or assistance. ”

The conditions of life and work for Tsiolkovsky changed radically after the October Revolution. In 1918 he became a member of the Academy, and in November 1921 he was allotted a personal pension. It became possible for him to devote himself completely to his scientific work.

During the 1920’s Tsiolkovsky continued his investigations in aeronautics, and he elaborated his theory of multistage rockets. He also began working out his theory of the flight of jet airplanes, devoting a number of papers to this question.

In 1921 Tsiolkovsky conceived the idea of building a transport vehicle that would be carried on a cushion of air. This idea was further developed in “Soprotivelenic vozdukha i skory poezd” (“Air Resistance an the Express Train,” 1927) and “Obshchie uslovia transporta” (“General Conditions for Transport,” 1934).

In the mid-1920’s, Tsiolkovsky’s works in rockt engineering and space flight began to win international recognition. Hermann Oberth, the German rocket technologist, wrote to Tsiolklovsky in 1929: “You have ignited the flame, and we shall not permit it to be extinguished; we shall make every effort so that the greatest dream of mankind might be fulfilled.”

Despite old age, Tsiolkovsky continued his scientific work, In “Dostizhenie stratosfery” (“Reaching the Stratosphere,” 1932), he formulated the requirements of explosive fuel for use in jet engines. In 1934 and 1935 he proposed using clusters of rockets in order to reach great speeds.

“The main motive of my life,” Tsiolkovsky wrote in evaluating his activity, “has been to . . . move humanity forward if only slightly. This is exactly why I have been interested in those things that never yielded either bread or strength. But I hope that my labors perhaps . . . may give to society mountains of bread and infinite power.”


Tsiolkovsky’s collected works were published as Sobranie sochineny. 5 vols. (Moscow, 1951–1967). On his life work, see Konstantin Eduardovich Tsiolkovsky (1857–1932) (Moscow-Leningard 1932), a jubilee collection published to commemorate his seventy-fitth birthday; and M. S. Arlazorov, K. E.Tsiolkovsky, egozhizn i deyatelnost (“. . . His Life and Work”; Moscow, 1962).

A. T. Grigorian

Tsiolkovsky, Konstantin Eduardovich

views updated May 21 2018


(18571935), Russian space technology expert.

Born in Izhevskoye, Tsiolkovsky was a pioneer of rocket technology and astronautics, known in Russia as cosmonautics. Tsiolkovsky might be termed the "Robert Goddard of Russia," after the American rocket expert, who, like Tsiolkovsky, began testing rockets in the first decade of the twentieth century.

Tsiolkovsky is generally credited with deducing for the first time the laws of motion of a rocket as a body of a variable mass in space without gravity. This, in turn, demonstrated the possibility of using rockets for interplanetary exploration. He also investigated the effect of air drag on rocket motion. Such theories and research became subjects of his writings, which included Space Rocket Trains, published in 1929, which explored the theory of multistage rockets.

Among Tsiolkovsky's major influences on future space flight, and in particular on the successful orbiting of the world's first sputnik (in October 1957), was his work on liquid-propellant engines. In such research and writing he developed the specifications for rocket-engine design. Modern rocket engines still incorporate many of his basic ideas.

Much attention is given in Tsiolkovsky's writings to problems of organizing interplanetary travel and its prospects. He argued that beginning with artificial earth satellites (sputniks), interplanetary stations and flights to the planets could become a way of establishing communities in outer space and adapting space for human needs.

With the advent of Soviet power in Russia, Tsiolkovsky's work received the full support of the state. In 1918 he was elected to the Socialist Academy of Science. Later honors included membership in Russia's main cosmonautics society and the Zhukovsky Air Force Academy. His collected scientific writings appeared in the USSR from 1951 through 1964.

See also: academy of sciences; space program


Petrovich, G. V. (2002). The Soviet Encyclopedia of Space Flight. Seattle, WA: University Press of the Pacific.

Albert L. Weeks

Konstantin Eduardovich Tsiolkovsky

views updated May 18 2018

Konstantin Eduardovich Tsiolkovsky


Russian rocket scientist who was an early pioneer of space travel research. In the 1890s Tsiolkovsky developed Russia's first wind tunnel to test aircraft aerodynamics. His passion for the stars led him to try his hand at science fiction writing, and his stories of rocket ships eventually evolved into a study of the potential for space travel. Tsiolkovsky's research in aerodynamics led him to theorize about the challenges of using rocket engines in space, including navigation and fuel supply maintenance. His "Tsiolkovsky Formula" formed the basis of contemporary astronautics, and paved the way for space exploration.

Tsiolkovsky, Konstantin Eduardovich

views updated Jun 11 2018

Tsiolkovsky, Konstantin Eduardovich (1857–1935) Russian aeronautical engineer. In 1898, he became the first person to stress the importance of liquid propellants in rockets. Tsiolkovsky also proposed the idea of using multi-stage rockets to overcome gravitation.