3d map of universe
The 3D map of the universe.University of Waterloo

A 3D map of the universe spanning two billion light years has been created, providing the most complete picture of space ever produced.

Astrophysicists at the University of Waterloo and the Institute d'Astrophysique de Paris say the spherical map of the universe will provide a greater understanding of the mysteries of the universe, such as the nature of dark matter.

Published in the journal Monthly Notices of the Royal Astronomical Society, the lighter blue and white areas of the map represent higher concentrations of galaxies. The red area is a supercluster known as the Shapley Concentration – the largest collection of galaxies in the near universe. Areas in medium blue are unexplored areas.

The map shows how the universe has features similar to a mountain range. Researcher Mike Hudson said: "The galaxy distribution isn't uniform and has no pattern. It has peaks and valleys much like a mountain range. This is what we expect if the large-scale structure originates from quantum fluctuations in the early universe."

The volume mapped is roughly circular - a bit like slicing an orange vertically from the edge through to the opposite edge. The location of the Milky Way Galaxy is in centre of the middle frame (marked SGZ=0) halfway through the movie.

Researchers now plan to enhance the map by getting more detailed samples of peculiar velocities – scientists have observed galaxies moving differently because the universe's expansion is not even. For example, the Milky Way and our closest neighbour Andromeda are moving at two million kilometres per hour.

Previous models of the universe have not fully accounted for this motion, and the team hopes to discover what structures are responsible for the peculiar velocities. Deviations in the motion of galaxies are important in determining the distribution of matter and dark matter on huge scales.

Knowing the location of motion and location of matter will help astrophysicists predict the universe's expansion, along with where and how much dark matter exists.

"A better understanding of dark matter is central to understanding the formation of galaxies and the structures they live in, such as galaxy clusters, superclusters and voids," Hudson said.