The U.S. Navy yesterday test fired an incredibly powerful new big gun designed to replace conventional weaponry aboard ships. Sci-fi fans will recognize its awesome power and futuristic technology.

The big gun uses electromagnetic energy instead of explosive chemical propellants to fire a projectile farther and faster. The railgun, as it is called, will ultimately fire a projectile more than 230 miles (370 kilometers) with a muzzle velocity seven times the speed of sound (Mach 7) and a velocity of Mach 5 at impact.

The test-firing, captured on video, took place Jan. 31 in Dahlgren, Va., and Navy officials called it the "world's most powerful electromagnetic railgun."

The Navy's current MK 45 five-inch gun, by contrast, has a range of less than 23 miles (37 kilometers).