U.S. researchers report they have generated the largest and most realistic simulations of the evolving universe yet, which will help astrophysicists better understand mysteries like galaxy formation, dark matter and dark energy.

Scientists from the University of California, Santa Cruz, and New Mexico State University in Las Cruces ran a program known as the Bolshoi simulation code for 18 days on Pleiades, the seventh most powerful supercomputer in the world, at the Ames Research Center in Mountain View, Calif.

Named Bolshoi, for the Russian word meaning “grand” or “great,” the simulation has taken four years to develop.

The simulation tries to track the progression of large-scale structures in space, and brings to light how coronas of dark matter encircle galaxies in the wide cosmos to provide the gravity that holds them together.

The simulation corroborates the accuracy of models that astronomers have built to clarify how the Big Bang theory initiated the source of subatomic particles and galaxies that inhabit our growing universe, said Joel Primack, head of the simulation program at UC-Santa Cruz.

In one sense, you might think the initial results are a little boring, because they basically show that our standard cosmological model works. What’s exciting is that we now have this highly accurate simulation that will provide the basis for lots of important new studies in the months and years to come, Primack said.

Astronomers have already estimated that dark matter accounts for more almost 80 percent of all matter in the universe.

The simulation signifies the nature and power of another mysterious force identified as dark energy, which is also vital to the established development of space, Primack stated.

These huge cosmological simulations are essential for interpreting the results of ongoing astronomical observations and for planning the new large surveys of the universe that are expected to help determine the nature of the mysterious dark energy,” said Anatoly Klypin, professor of astronomy at New Mexico State, who wrote the computer code for the simulation.

We've released a lot of the data so that other astrophysicists can start to use it. So far it's less than 1 percent of the actual output, because the total output is so huge, but there will be additional releases in the future, Primack said.

Two principal research papers have been produced as results of the Bolshoi simulation. They will be published in the Astrophysical Journal.

The whole simulation is based on the most recent adaptation of a map of the early cosmos created almost 10 years ago by a satellite called the Wilkinson Microwave Anisotropy Probe.

It uncovered microwave radiation that was left like a weak reverberation from the Big Bang, and demonstrated how it indicated the beginnings of the universe, which is more than 13 billion years ago.

One of the research works accepted for publication focuses on the attributes of the halos of dark matter that surround the galaxies, while the other deals with the profusion and properties of the galaxies in the replication.