IBM’s Blue Gene/L system, at 70.72 teraflops, was officially named the fastest in the world Monday by the Top500 project, an independent group of university computer scientists.

SGI’s Project Columbia, being built at NASA Ames Research Center, came in second place with 51.87 teraflops.

Blue Gene/L will be installed next year at Lawrence Livermore National Laboratory in Livermore, Calif., where it will be used to study the nation’s nuclear stockpile and perform other research. Currently, it’s just a quarter of its planned size of 360 teraflops.