Blasted into Space from a Giant Air Gun

When Jules Verne wrote about a gigantic gun that could be used to launch people into space in the 19th century, no one expected it to become a reality. Now physicist John Hunter has outlined the design of such a gun that he says could slash the cost of putting cargo into orbit. The gun is based on a smaller device Hunter helped to build in the 1990s while at the Lawrence Livermore National Laboratory (LLNL) in California. With a barrel 47 metres long, it used compressed hydrogen gas to fire projectiles weighing a few kilograms at speeds of up to 3 kilometres per second