From The Earth To The Moon - Technical Feasibility of A Space Cannon

Technical Feasibility of A Space Cannon

In his 1903 publication on space travel, Konstantin Tsiolkovsky refuted Verne's idea of using a cannon for space travel. He concluded that a gun would have to be impossibly long. The gun in the story would subject the payload to about 22000 g of acceleration (see formula). However, he was nevertheless inspired by the story and developed the theory of spaceflight.

Gerald Bull and the Project HARP proved after 1961 that a cannon can shoot a 180 kg (400 lb) projectile to an altitude of 180 kilometres (110 mi) and reach 32 percent of the needed escape velocity. Additionally, during the Plumbbob nuclear test series, a 900 kg (2,000 lb) capping plate made of steel was blasted away and never found. It has been speculated that the plate entered outer space because its speed was estimated to be between two and six times the escape velocity, but engineers believe it melted in the atmosphere.