
Space weapons are
weapon
A weapon, arm, or armament is any implement or device that is used to deter, threaten, inflict physical damage, harm, or kill. Weapons are used to increase the efficacy and efficiency of activities such as hunting, crime (e.g., murder), law ...
s used in
space warfare
Space warfare is combat in which one or more belligerents are in outer space. The scope of space warfare includes ''ground-to-space warfare'', such as attacking satellites from the Earth; ''space-to-space warfare'', such as satellites attacki ...
. They include weapons that can attack space systems in orbit (for example,
anti-satellite weapon
Anti-satellite weapons (ASAT) are space weapons designed to incapacitate or destroy satellites for Military strategy, strategic or Military tactics, tactical purposes. Although no ASAT system has been utilized in warfare, a few countries (China, ...
s),
attack targets on the earth from space or
disable missiles travelling through space. In the course of the
militarisation of space
The militarisation of space involved 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 Sov ...
, such weapons were developed mainly by the contesting
superpower
Superpower describes a sovereign state or supranational union that holds a dominant position characterized by the ability to Sphere of influence, exert influence and Power projection, project power on a global scale. This is done through the comb ...
s during the
Cold War
The Cold War was a period of global Geopolitics, geopolitical rivalry between the United States (US) and the Soviet Union (USSR) and their respective allies, the capitalist Western Bloc and communist Eastern Bloc, which lasted from 1947 unt ...
, and some remain under development today. Space weapons are also a central theme in
military science fiction
Military science fiction is a subgenre of science fiction and military fiction that depicts the use of science fiction technology, including spaceships and science fiction weapons, weapons, for military purposes and usually principal characters ...
and sci-fi video games.
Space-to-space weapons
The Soviet
Almaz
The Almaz () program was a highly secret Soviet Union, Soviet military space station program, begun in the early 1960s.
Three crewed military reconnaissance stations were launched between 1973 and 1976: Salyut 2, Salyut 3 and Salyut 5.
To co ...
secret military
space station
A space station (or orbital station) is a spacecraft which remains orbital spaceflight, in orbit and human spaceflight, hosts humans for extended periods of time. It therefore is an artificial satellite featuring space habitat (facility), habitat ...
program was equipped with a fixed
23mm autocannon to prevent hostile interception or boarding by hostile forces. This was the first and so far the only space-to-space weapon to be fired in orbit.
The Soviet uncrewed
Polyus weapons platform was designed to be equipped with a megawatt
carbon-dioxide laser and a self-defense cannon.
Earth-to-space weapons
Anti-satellite weapon
Anti-satellite weapons (ASAT) are space weapons designed to incapacitate or destroy satellites for Military strategy, strategic or Military tactics, tactical purposes. Although no ASAT system has been utilized in warfare, a few countries (China, ...
s, which are primarily surface-to-space and air-to-space missiles, have been developed by the United States, the
USSR
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...
/Russia, India and the People's Republic of China. Multiple test firings have been done as part of recent Chinese and U.S test programs that involved destroying an orbiting satellite.
In general, the use of explosive and
kinetic kill systems is limited to relatively low altitudes due to
space debris
Space debris (also known as space junk, space pollution, space waste, space trash, space garbage, or cosmic debris) are defunct human-made objects in spaceprincipally in Earth orbitwhich no longer serve a useful function. These include dere ...
issues and so as to avoid leaving debris from launch in orbit.
Strategic Defense Initiative
On March 23, 1983, President
Ronald Reagan
Ronald Wilson Reagan (February 6, 1911 – June 5, 2004) was an American politician and actor who served as the 40th president of the United States from 1981 to 1989. He was a member of the Republican Party (United States), Republican Party a ...
proposed the
Strategic Defense Initiative
The Strategic Defense Initiative (SDI) was a proposed missile defense system intended to protect the United States from attack by ballistic nuclear missiles. The program was announced in 1983, by President Ronald Reagan. Reagan called for a ...
, a research program with a goal of developing a defensive system which would destroy enemy
ICBMs. The defensive system was nicknamed
Star Wars
''Star Wars'' is an American epic film, epic space opera media franchise created by George Lucas, which began with the Star Wars (film), eponymous 1977 film and Cultural impact of Star Wars, quickly became a worldwide popular culture, pop cu ...
, after the movie, by its detractors.
Some concepts of the system included
Brilliant Pebbles
Brilliant Pebbles was a space-based ballistic missile defense (BMD) system proposed by Lowell Wood and Edward Teller of the Lawrence Livermore National Laboratory (LLNL) in 1987, near the end of the Cold War. The system would consist of thousan ...
, which were Kinetic Kill Vehicles, essentially small rockets launched from satellites toward their targets (a warhead, warhead bus, or even an upper stage of an ICBM). Other aspects included
satellite
A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scient ...
s in
orbit
In celestial mechanics, an orbit (also known as orbital revolution) is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an ...
carrying powerful
laser weapon
A laser weapon is a type of directed-energy weapon that uses lasers to inflict damage. Whether they will be deployed as practical, high-performance military weapons remains to be seen. One of the major issues with laser weapons is atmospheric ...
s,
plasma weapon
A directed-energy weapon (DEW) is a ranged weapon that damages its target with highly focused energy without a solid projectile, including lasers, microwaves, particle beams, and sound beams. Potential applications of this technology include w ...
s, or
particle beam
A particle beam is a stream of charged particle, charged or neutral particles other than photons. In Particle accelerator, particle accelerators, these particles can move with a velocity close to the speed of light. There is a difference between ...
s. When a missile launch was detected, the satellite would fire at the missile (or warheads) and destroy it. Although no real hardware was ever manufactured for deployment, the military did test the use of lasers mounted on
Boeing 747s to destroy missiles in the 2000s, however these were discontinued due to practical limitations of keeping a constant fleet airborne near potential launch sites due to the lasers range limitations keeping a small number from being sufficient. The tests took place at
Edwards Air Force Base
Edwards Air Force Base (AFB) is a United States Air Force installation in California. Most of the base sits in Kern County, California, Kern County, but its eastern end is in San Bernardino County, California, San Bernardino County and a souther ...
.
Space-to-Earth weapons
Orbital weaponry

Orbital weaponry is any weapon that is in
orbit
In celestial mechanics, an orbit (also known as orbital revolution) is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an ...
around a large body such as a planet or moon. As of December 2022, there are no known operative orbital weapons systems, but several nations have deployed orbital surveillance networks to observe other nations or armed forces. Several orbital weaponry systems were designed by the United States and the
Soviet Union
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...
during the
Cold War
The Cold War was a period of global Geopolitics, geopolitical rivalry between the United States (US) and the Soviet Union (USSR) and their respective allies, the capitalist Western Bloc and communist Eastern Bloc, which lasted from 1947 unt ...
. During World War II
Nazi Germany
Nazi Germany, officially known as the German Reich and later the Greater German Reich, was the German Reich, German state between 1933 and 1945, when Adolf Hitler and the Nazi Party controlled the country, transforming it into a Totalit ...
was also developing plans for an orbital weapon called the
Sun gun, an orbital mirror that would have been used to focus and weaponize beams of sunlight.
Development of orbital weaponry was largely halted after the entry into force of the
Outer Space Treaty
The Outer Space Treaty, formally the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies, is a Multilateralism, multilateral treaty that forms the bas ...
and the
SALT II
The Strategic Arms Limitation Talks (SALT) were two rounds of bilateral conferences and corresponding international treaties involving the United States and the Soviet Union. The Cold War superpowers dealt with arms control in two rounds of ...
treaty. These agreements prohibit
weapons of mass destruction
A weapon of mass destruction (WMD) is a Biological agent, biological, chemical weapon, chemical, Radiological weapon, radiological, nuclear weapon, nuclear, or any other weapon that can kill or significantly harm many people or cause great dam ...
from being placed in space. As other weapons exist, notably those using
kinetic bombardment, that would not violate these treaties, some private groups and government officials have proposed a
Space Preservation Treaty which would ban the placement of any weaponry in outer space.
The United States is seeking to develop Space-Based Interceptors for missile defense.
Orbital bombardment
Orbital bombardment is the act of attacking targets on a planet, moon or other
astronomical object
An astronomical object, celestial object, stellar object or heavenly body is a naturally occurring physical entity, association, or structure that exists within the observable universe. In astronomy, the terms ''object'' and ''body'' are of ...
from
orbit
In celestial mechanics, an orbit (also known as orbital revolution) is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an ...
around the object, rather than from an aircraft, or a platform beyond orbit. It has been proposed as a means of attack for several weapons systems concepts, including
kinetic bombardment and as a nuclear delivery system.
During the
Cold War
The Cold War was a period of global Geopolitics, geopolitical rivalry between the United States (US) and the Soviet Union (USSR) and their respective allies, the capitalist Western Bloc and communist Eastern Bloc, which lasted from 1947 unt ...
, the
Soviet Union
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...
deployed a
Fractional Orbital Bombardment System from 1968 to 1983. Using this system, a
nuclear
Nuclear may refer to:
Physics
Relating to the nucleus of the atom:
*Nuclear engineering
*Nuclear physics
*Nuclear power
*Nuclear reactor
*Nuclear weapon
*Nuclear medicine
*Radiation therapy
*Nuclear warfare
Mathematics
* Nuclear space
*Nuclear ...
warhead could be placed in
low Earth orbit
A low Earth orbit (LEO) is an geocentric orbit, orbit around Earth with a orbital period, period of 128 minutes or less (making at least 11.25 orbits per day) and an orbital eccentricity, eccentricity less than 0.25. Most of the artificial object ...
, and later de-orbited to hit any location on the Earth's surface. While the Soviets deployed a working version of the system, they were forbidden by the
Outer Space Treaty
The Outer Space Treaty, formally the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies, is a Multilateralism, multilateral treaty that forms the bas ...
to place live warheads in space. The fractional orbital bombardment system was phased out in January 1983 in compliance with the
SALT II
The Strategic Arms Limitation Talks (SALT) were two rounds of bilateral conferences and corresponding international treaties involving the United States and the Soviet Union. The Cold War superpowers dealt with arms control in two rounds of ...
treaty of 1979, which, among other things, prohibited the deployment of systems capable of placing
weapons of mass destruction
A weapon of mass destruction (WMD) is a Biological agent, biological, chemical weapon, chemical, Radiological weapon, radiological, nuclear weapon, nuclear, or any other weapon that can kill or significantly harm many people or cause great dam ...
in such a partial orbit.
Orbital bombardment systems with conventional warheads are permitted under the terms of
SALT II
The Strategic Arms Limitation Talks (SALT) were two rounds of bilateral conferences and corresponding international treaties involving the United States and the Soviet Union. The Cold War superpowers dealt with arms control in two rounds of ...
. Some of the proposed systems rely on large
tungsten carbide
Tungsten carbide (chemical formula: ) is a carbide containing equal parts of tungsten and carbon atoms. In its most basic form, tungsten carbide is a fine gray powder, but it can be pressed and formed into shapes through sintering for use in in ...
/
uranium
Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Ura ...
cermet rods dropped from orbit and depend on
kinetic energy
In physics, the kinetic energy of an object is the form of energy that it possesses due to its motion.
In classical mechanics, the kinetic energy of a non-rotating object of mass ''m'' traveling at a speed ''v'' is \fracmv^2.Resnick, Rober ...
, rather than explosives, but their mass makes them prohibitively difficult to transport to orbit.
As of 2020 the only true orbital bombardment in history has been executed for scientific purposes. On 5 April 2019 the Japanese ''
Hayabusa2'' robotic space probe released an explosive device called an "impactor" from space onto the surface of asteroid
162173 Ryugu, in order to collect debris released by the explosion. The mission was successful and ''Hayabusa2'' retrieved valuable samples of the celestial body which it brought back to Earth.
In fiction
Fictional or real space weapons in various forms are often prominently featured in
science fiction
Science fiction (often shortened to sci-fi or abbreviated SF) is a genre of speculative fiction that deals with imaginative and futuristic concepts. These concepts may include information technology and robotics, biological manipulations, space ...
, particularly in
military science fiction
Military science fiction is a subgenre of science fiction and military fiction that depicts the use of science fiction technology, including spaceships and science fiction weapons, weapons, for military purposes and usually principal characters ...
and in
video game
A video game or computer game is an electronic game that involves interaction with a user interface or input device (such as a joystick, game controller, controller, computer keyboard, keyboard, or motion sensing device) to generate visual fe ...
s with a sci-fi theme.
See also
*
Ivan's hammer
*
Laser weapon
A laser weapon is a type of directed-energy weapon that uses lasers to inflict damage. Whether they will be deployed as practical, high-performance military weapons remains to be seen. One of the major issues with laser weapons is atmospheric ...
References
External links
Nuclear Files.orgBasic facts and issues regarding space weapons
SpaceDebate.org– collection of articles, quotes, and links on the debate over space weapons
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