Astrophysicists from the University of Zurich in Switzerland have built the largest simulation of the universe yet. The simulation, which was described in Computational Astrophysics and Cosmology, enables scientists to see how dark matter interacts with the universe. The photo above is part of the simulation, which highlights the dark matter halos in yellow — the dark matter that hypothetically surrounds galaxies.

How big? The simulation models more than 25 billion virtual galaxies.

Why it matters: The simulation will serve as a calibrator to help the Euclid satellite gather information from the universe. The simulation with help frame what Euclid will look for in its investigation into dark matter and dark energy. The satellite is set to launch in 2020.

How to see dark matter: Scientists believe dark matter and dark energy constitute 95% of our universe — the other 5% is what we can see, but this dark matter has remained mostly a mystery. Euclid won't be able to literally see the dark matter, but it will be looking for changes in the light as it travels the Universe. The astrophysicists' simulation predicts how dark matter and dark energy operate, which helps frame the kind of dark matter effects Euclid should be looking for and measuring.

Go deeper: Read the press release with details on how the simulation was built and Euclid's goals, here.