Astronomers have created the largest and most realistic simulated version of the universe yet. The simulation provides a new look at the past and present of the cosmos on a scale and in detail impossible until now, and if you feel like it, they have made it freely available for anyone to download.
As reported in the Monthly Notices of the Royal Astronomical Society, the simulation is called Uchuu (meaning "outer space" in Japanese). The virtual universe is contained in a cube with each side an unprecedented 9.63 billion light-years and made of 2.1 trillion particles. That’s not enough to simulate planets and individual stars but it allowed the international team of researchers to simulate galaxy interactions at an incredible level of detail.
Realistic simulations like this allow us to test our theories of the universe. As it stands, evidence suggests that the cosmos is dominated by two mysterious components. The matter that made us and stars is only 5 percent of the total content. Twenty-five percent is dark matter, an invisible substance that surrounds galaxies, and the rest is dark energy, which is believed to be responsible for the accelerated expansion of the universe.
Uchuu allows astronomers to see how the proportions of these different components affect the structures in the universe. The simulation covers the assemblage of galaxies and galaxy clusters over the 13.8 billion years since the Big Bang.
“Uchuu is like a time machine: we can go forward, backward and stop in time, we can ''zoom in'' on a single galaxy or ''zoom out'' to visualize a whole cluster, we can see what is really happening at every instant and in every place of the universe from its earliest days to the present, being an essential tool to study the cosmos,” Julia F. Ereza, a graduate researcher at the Instituto de Astrofísica de Andalucía, said in a statement.
Uchuu was created using the supercomputer ATERUI II, which is considered the world’s best among those dedicated to astronomy.
"To produce Uchuu we have used ... all 40,200 processors (CPU cores) available exclusively for 48 hours each month. Twenty million supercomputer hours were consumed, and 3 Petabytes of data were generated, the equivalent of 894,784,853 pictures from a 12-megapixel cell phone," said lead author Tomoaki Ishiyama, an associate professor at Chiba University. Ishiyama developed the code used to generate Uchuu.
The creation of such a simulated universe will help with the exciting, and very large, data set expected to be delivered by the next generation of observatories over the coming decade.