The militarisation of space is the placement and development of weaponry and military technology in outer space. The early exploration of space in the mid-20th century had, in part, a military motivation, as the United States and the Soviet Union used it as an opportunity to demonstrate ballistic missile technology and other technologies having the potential for military application. Outer space has since been used as an operating location for military spacecraft such as imaging and communications satellites, and some ballistic missiles pass through outer space during their flight. As yet, however, weapons have not been stationed in space, with the exception of the Almaz space station and small handguns carried by Russian cosmonauts (for post-landing, pre-recovery use).
As early as 1927 members of the Verein für Raumschiffahrt (VfR) ("Spaceflight Society") had started experimenting with liquid-fuel rockets. Rockets using a solid propellant had been used as weapons by all sides in World War I, and as a result, the Treaty of Versailles forbade solid fuel rocket research in Germany. By 1932 the Reichswehr started taking notice of their developments for potential long-range artillery use, and a team led by General Walter Dornberger was shown a test vehicle designed and flown by Wernher von Braun. Although the rocket was of limited ability, Dornberger saw von Braun's genius and pushed for him to join the military.
Von Braun did so, as eventually did most of the other members of the society. In December 1934 von Braun scored another success with the flight of the A2 (A for Aggregat) rocket, a small model powered by ethanol and liquid oxygen, with work on the design continuing in an attempt to improve reliability. Many different liquid fuels had been developed, but the German military specifically encouraged the use of ethanol as a rocket fuel because Germany had always been hampered by a shortage of crude oil-based fuels. Throughout World War II, a wide variety of military rockets were fuelled by ethanol that were derived primarily from potatoes.