Los Alamos National Laboratory Advanced Simulation and Computing (ASC) Program
Ensuring the safety and reliability of the nation's nuclear weapons stockpile


ASC Platforms provide an integrated system of hardware and software that enables scientists to run simulations and calculations in support of the Stockpile Stewardship Program. Los Alamos has a long history of top-performing platforms.
Crossroads (placeholder image)


Crossroads, the third Advanced Technology (AT) system in the Advanced Simulation and Computing (ASC) Program, will be critical to the success of the National Nuclear Security Administration (NNSA) Stockpile Stewardship Program (SSP). Crossroads will support the highest fidelity of next-generation weapons simulations and meet NNSA Defense Programs’ mission needs. In addition, Crossroads will explore and exploit new technologies with a focus on improving efficiency in three key areas: application performance, workflow, and application development. | Project Site.

Los Alamos Historical Platforms

Trinity supercomputer


Trinity is designed to provide increased computational capability for the NNSA Nuclear Security Enterprise in support of ever-demanding workloads, e.g., increasing geometric and physics fidelities while maintaining expectations for time to solution. | Project Site

Roadrunner supercomputer


Roadrunner was the first computer to reach petaflop speed. Its unique architecture inspired new supercomputer designs around the world, pushing computer speed and capability to greater heights. | Read more »

Cielo supercomputer


The Cielo supercomputer was designed to provide increased physics and geometric fidelities for the weapons program, while at the same time maintaining time to solution. Installed in 2010, Cielo provided the production workload for NNSA’s largest three dimensional calculation over the next 5 years.

Q Machine


The Q system was the first computer to be installed in the SCC. With a speed of over 20 teraFLOPS. It enabled the first million-atom simulation in biology for the molecular mechanism of the genetic code, defining a new “state-of-the art” in biomolecular simulation. The Q system was crucial in meeting some advance ASCI application milestones in addition to providing the tri-lab community a powerful platform for running stewardship applications through a classified distance computing network.

Blue Mountain supercomputer

Blue Mountain

The Blue Mountain system, installed at LANL in 1998, was used to produce the first three dimensional likeness of how a nuclear weapon would perform if exploded. It was the world’s fastest computer in 1998.

Cielo supercomputer


The CM-5 system consisted of a set of processing nodes usually divided into smaller groups called partitions. The CM-5 was the first large scale massively parallel production system used at LANL. It was number one on the first TOP500 Supercomputer performance list in 1993.

Cray-1 supercomputer


The first Cray-1 system was installed at Los Alamos National Laboratory in 1976. It was the first of numerous models supplied by Cray Research that provided the bulk of LANL’s production supercomputing over the next several decades. The vector supercomputing capability was well suited to the Laboratory’s weapons simulations.

Maniac computer


The Mathematical Analyzer, Numerical Integrator And Computer was the first digital supercomputer at Los Alamos National Laboratory. MANIAC was built under the direction of Nicholas Metropolis and based on the von Neumann architecture of the IAS. MANIAC did the calculations for ”Project Mike,” which produced the first hydrogen bomb.