Simulating galaxy creation

Simulating galaxy creation

An international team of astronomers has developed a simulation of the universe in which realistic galaxies are created — their mass, size, and age are similar to those of observed galaxies.

Previous computer simulations had limited success because their simulations were too old, too spherical, and either too massive or too small.

In the new study, by astronomers based at Durham University and Leiden University in the Netherlands, the galaxies formed in the EAGLE-simulation (Evolution and Assembly of GaLaxies and their Environments) are a much closer facsimile of real galaxies, thanks to modeling strong galactic winds.

Powered by stars, supernova explosions, and supermassive black holes, the winds blow away the gas supply needed for the formation of stars. As a result, EAGLE’s galaxies are also lighter and younger because fewer stars form and they form later. The sizes and shapes of the thousands of galaxies that form in the EAGLE simulation are also similar to those of galaxies that astronomers actually observe in the Universe.

The simulations took several months to run at the “Cosmology Machine” in Durham and at “Curie” in Paris, among the largest computers used for scientific research in the U.K. and France, respectively.

Astronomers can now use the results to study the evolution of individual galaxies in detail, from almost 14 billion years ago until now.

“The universe generated by the computer is just like the real thing,” says co-author Richard Bower from Durham University. “There are galaxies everywhere, with all the shapes, sizes and colors I’ve seen with the world’s largest telescopes. It is incredible. In the EAGLE universe I can even press a button to make time run backwards,”