The Stonehenge Turret Network, frequently known in shorthand as Stonehenge, was a planetary defense complex created by the Allies to destroy asteroids and starships. Stonehenge was based on a circular facility divided in eight portions, each of which housed a railgun. The weapons, officially called the "120cm-Caliber-Anti-Surface-And-Air Gunpowder-And-Electromagnetic-Propelling Semiautomatic-Fixated Guns", operated on a hybrid energy principle, using gunpowder to propel projectiles, which are then fired with electromagnetic energy. The cannons were considered "electromagnetic launchers" by their creators instead or railguns, based on their combined propellants. Capable of achieving speeds of 6 kilometers per second, the choice of hybrid propellants was to prevent Joule heat from melting the barrels, as well as the excessive costs related to the use of pure electricity.