---
title: "Konstantin Tsiolkovsky"
chunk: 2/4
source: "https://en.wikipedia.org/wiki/Konstantin_Tsiolkovsky"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T04:03:32.859220+00:00"
instance: "kb-cron"
---

Tsiolkovsky stated that he developed the theory of rocketry only as a supplement to philosophical research on the subject. He wrote more than 400 works including approximately 90 published pieces on space travel and related subjects. Among his works are designs for rockets with steering thrusters, multistage boosters, space stations, airlocks for exiting a spaceship into the vacuum of space, and closed-cycle biological systems to provide food and oxygen for space colonies.
Tsiolkovsky's first scientific study dates back to 1880–1881. He wrote a paper called "Theory of Gases," in which he outlined the basis of the kinetic theory of gases, but after submitting it to the Russian Physico-Chemical Society (RPCS), he was informed that his discoveries had already been made 25 years earlier. Undaunted, he pressed ahead with his second work, "The Mechanics of the Animal Organism". It received favorable feedback, and Tsiolkovsky was made a member of the Society. Tsiolkovsky's main works after 1884 dealt with four major areas: the scientific rationale for the all-metal balloon (airship), streamlined airplanes and trains, hovercraft, and rockets for interplanetary travel.
In 1892, he was transferred to a new teaching post in Kaluga where he continued to experiment. During this period, Tsiolkovsky began working on a problem that would occupy much of his time during the coming years: an attempt to build an all-metal dirigible that could be expanded or shrunk in size.
Tsiolkovsky developed the first aerodynamics laboratory in Russia in his apartment. In 1897, he built the first Russian wind tunnel with an open test section and developed a method of experimentation using it. In 1900, with a grant from the Academy of Sciences, he made a survey using models of the simplest shapes and determined the drag coefficients of the sphere, flat plates, cylinders, cones, and other bodies. 
Tsiolkovsky's work in the field of aerodynamics was a source of ideas for Russian scientist Nikolay Zhukovsky, the father of modern aerodynamics and hydrodynamics. Tsiolkovsky described the airflow around bodies of different geometric shapes. Because the RPCS did not provide any financial support for this project, he was forced to pay for it largely out of his own pocket.
Tsiolkovsky studied the mechanics of lighter-than-air powered flying machines. He first proposed the idea of an all-metal dirigible and built a model of it. The first printed work on the airship was "A Controllable Metallic Balloon" (1892), in which he gave the scientific and technical rationale for the design of an airship with a metal sheath. Tsiolkovsky was not supported on the airship project, and the author was refused a grant to build the model. An appeal to the General Aviation Staff of the Russian army also had no success. 
In 1892, he turned to the new and unexplored field of heavier-than-air aircraft. Tsiolkovsky's idea was to build an airplane with a metal frame. In the article "An Airplane or a Birdlike (Aircraft) Flying Machine" (1894) are descriptions and drawings of a monoplane, which in its appearance and aerodynamics anticipated the design of aircraft that would be constructed 15 to 18 years later. In an Aviation Airplane, the wings have a thick profile with a rounded front edge and the fuselage is faired. 
Work on the airplane, as well as on the airship, did not receive recognition from the official representatives of Russian science, and Tsiolkovsky's further research had neither monetary nor moral support. In 1914, he displayed his models of all-metal dirigibles at the Aeronautics Congress in St. Petersburg, but was met with a lukewarm response.
Disappointed at this, Tsiolkovsky gave up on space and aeronautical problems with the onset of World War I and turned his attention to the problem of alleviating poverty. This occupied his time during the war years until the Russian Revolution in 1917.
Starting in 1896, Tsiolkovsky systematically studied the theory of motion of rocket apparatus. Thoughts on the use of the rocket principle in the cosmos were expressed by him as early as 1883, and a rigorous theory of rocket propulsion was developed in 1896. Tsiolkovsky derived the formula, which he called the "formula of aviation", now known as Tsiolkovsky rocket equation, establishing the relationship between:

change in the rocket's speed (
  
    
      
        Δ
        v
      
    
    {\displaystyle \Delta v}
  
)
exhaust velocity of the engine (
  
    
      
        
          v
          
            e
          
        
      
    
    {\displaystyle v_{e}}
  
)
initial (
  
    
      
        
          m
          
            0
          
        
      
    
    {\displaystyle m_{0}}
  
) and final (
  
    
      
        
          m
          
            f
          
        
      
    
    {\displaystyle m_{f}}
  
) mass of the rocket

  
    
      
        Δ
        v
        =
        
          v
          
            e
          
        
        ln
        ⁡
        
          
            
              m
              
                0
              
            
            
              m
              
                f
              
            
          
        
      
    
    {\displaystyle \Delta v=v_{e}\ln {\frac {m_{0}}{m_{f}}}}
  

After writing out this equation, Tsiolkovsky recorded the date: 10 May 1897. In the same year, the formula for the motion of a body of variable mass was published in the thesis of the Russian mathematician I. V. Meshchersky ("Dynamics of a Point of Variable Mass," I. V. Meshchersky, St. Petersburg, 1897).
His most important work, published in May 1903, was Exploration of Outer Space by Means of Rocket Devices (Russian: Исследование мировых пространств реактивными приборами). Tsiolkovsky calculated, using the Tsiolkovsky equation, that the horizontal speed required for a minimal orbit around the Earth is 8,000 m/s (5 miles per second) and that this could be achieved by means of a multistage rocket fueled by liquid oxygen and liquid hydrogen. In the article "Exploration of Outer Space by Means of Rocket Devices", it was suggested for the first time that a rocket could perform space flight. In this article and its sequels (1911 and 1914), he developed some ideas of missiles and considered the use of liquid rocket engines.
The outward appearance of Tsiolkovsky's spacecraft design, published in 1903, was a basis for modern spaceship design.  The design had a hull divided into three main sections. The pilot and copilot would occupy the first section, while the second and third sections held the liquid oxygen and liquid hydrogen needed to fuel the spacecraft.