The Bolshoi simulation is the most accurate cosmological simulation of the evolution of the large-scale structure of the universe yet made.
The starting point for Bolshoi was the best ground- and space-based observations, including NASA's long-running and highly successful WMAP Explorer mission that has been mapping the light of the Big Bang in the entire sky. One of the world's fastest supercomputers then calculated the evolution of a typical region of the universe a billion light years across. The Bolshoi simulation took 6 million cpu hours to run on the Pleiades supercomputer—recently ranked as seventh fastest of the world's top 500 supercomputers—at NASA Ames Research Center.