What weapons could be used in a real-life space war?

Space, the final frontier...of warfare? Science fiction tales often center around the militarization of space, with lasers and torpedoes made of light racing past (and through) battleships and star destroyers.

But what about reality? Soviet and U.S. governments worked on a variety of space warfare projects during the Cold War, but were any of them functional? Let's take a look at those weapons that could blow satellites out of the sky, a space station rumored to be armed with a battleship cannon, and the Soviets' fears of a space shuttle that would drop a nuke on Moscow.

The top image: Rob Emery's homemade Colonial Viper, which will not be seeing active service anytime soon.

What weapons could be used in a real-life space war?S

Anti-Satellite Weaponry
The only publicly acknowledged use of weapons in space comes through the application of conventional explosives and kinetic weapons to eliminate satellites in low earth orbit.

The USSR developed the first piece of technology able to destroy an orbiting satellite through a system of conventional explosives carried by a Tsyklon-2 rocket, with a successful hit recorded in the late 1960s.

The USSR also launched a "hit-recording" satellite, the DS-P1-M, in 1970 to determine the efficiency of their efforts.

Not to be left behind in the Cold War, the United States followed suit by launching a missile from an F-15 to eliminate the P78-1 satellite, a gamma ray spectroscopy satellite orbiting 350 miles above the planet, in 1985 in a show of similar weapon capability.

What weapons could be used in a real-life space war?S

Space Debris
In 2007, the People's Republic of China used an SC-19 ASAT missile to hit the FY-1C, a weather satellite the size of a refrigerator orbiting at approximately 550 miles.

The height of the hit caused some concern, as the debris from the satellite is high enough to remain in orbit around the earth for a significant amount of time, with initial reports showing a debris ring circling the Earth a month after the satellite's destruction.

The use of anti-satellite weaponry is a concern due to the scattering of space debris in low earth orbit. This debris leads to the destruction of other satellites, and could cause problems for future generations of space travelers.

The United States drew considerable criticism for the destruction of a failing satellite in 2008. The satellite posed no threat upon re-entry, but hydrazine fuel within the satellite could hurt humans near the crash site. Exposure to high levels of hydrazine is associated with lung, central nervous system, and kidney damage, so the U.S. government destroyed the satellite, vaporizing the hydrazine roughly 100 miles above the Earth.

The Space Shuttle As A Nuclear Bomb Delivery Vehicle
During the height of the Cold War, Soviet suspicions led some government leaders to view the United States Space Shuttle program as a thinly veiled nuclear payload delivery device. Soviet space program leader Leonid Brezhnev believed the U.S. shuttle aimed to take off from a California Air Force base and orbit the Earth only once, with the shuttle avoiding conventional Soviet defense systems and dropping a nuclear bomb over Moscow once in the proper orbit position.

Use Of Terrestrial Guns In Space
The United States and Russian space programs send astronauts into space armed with handguns — these guns are included to protect astronauts if they land in an unusual or hostile environment.

Rumors surrounded the attachment of a 23-mm cannon to the Soviet space station Salyut 3, a mysterious space station launched with an intent to militarize space. Papel Popovich, the commander of a Soyuz flight to Salyut 3 confirms the presence of a cannon attached to the space station, but this is not confirmed by any other sources, and the cannon is not present on later Salyut models.

Where Are The Lasers?
When Space Shuttle Challenger orbited over the Russian city of Balkhash in 1984, several communication systems ceased to operate along with several key pieces of equipment. The city of Balkhash is the site of Terra-3, a Russian laser testing site, raising suspicions of an early test of Russian laser weaponry on an orbiting vehicle. Terra-3 is also associated with the "blinding" of several United States spy satellites monitoring the USSR in the 1970s and 1980s.

The United States Strategic Defense Initiative, the descendant of Reagan-era "Star Wars" space policy, aimed to arm satellites with anti-missile weaponry including lasers, particle beams, and rail guns. However, none of these systems are in use.

Purely A Defensive Measure?
Akin to nuclear proliferation, the development of space weaponry is a defensive countermeasure, an act that prevents other governments from using similar weaponry. Offensive uses of space weaponry (other than the suggested Russian laser tests) are nonexistent, with several treaties in place to prevent the use of weapons of mass destruction in space. At the moment, space is safe, unless you wander into some floating satellite debris.

Images courtesy of NASA, CC sources, Paul E. Reynolds (USAF), and the NASA Orbital Debris Program Office. Sources linked within the article.