Number 169 (Story #5), March 17, 1994 by Phillip F. Schewe and Ben Stein A HYPERVELOCITY LAUNCHER has accelerated a quarter-inch disk of metal to a velocity of 15.8 km/sec, or about 36,000 miles per hour, a record for a macroscopic object. For comparison, the Space Shuttle's orbit velocity is 17,500 mph, while the velocity for total escape from the Earth is 25,000 mph. The tremendous acceleration ensues from the following sequence: a gun fires a piston, which compresses a column of hydrogen gas, which moves a specially-sculpted impactor down a barrel where it strikes the projectile. The launcher, developed at Sandia (Philip Stanton, 505-845-8439), is currently used for studying the effect of space debris collisions with the prospective orbiting space station. (Sandia news release, 9 Mar.)