Astrophysicists have created a huge 3D map of the universe around us that spans nearly two billion light years from either end, as this is now the most complete picture of our cosmic point in the galaxy.The map consists of galaxy super clusters that will now help scientists understand how matter is better distributed across the universe, as it provides key insights into dark matter and gravity’s effect on large masses.
Professor Mike Hudson, Jonathan Carrick and Stephen Turnbull, of the Department of Physics and Astronomy at the University of Waterloo, and Guilhem Lavaux the Institute d’Astrophysique de Paris of the Centre national de la recherche scientifique of France, created the map. Professor Hudson is also an affiliate member of the Perimeter Institute for Theoretical Physics.
“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,” said Hudson, also associate dean of science. The map is shown online in the peer to peer-review journal of the Monthly Notices of the Royal Astronomical Society, who are one the leading journals, in the research of astrophysics and astronomy.
So what does this show us?
The lighter blue and white areas of the map characterize the greater concentration of galaxies. While the red area is the known super cluster called the Shapley Concentration. As this is the largest collection of galaxies in the nearby universe, the unexplored areas appear in average blue on the map. By knowing their location and the motion of matter in the surrounding universe predictions can be made to how the universe is going to expand in the future, while also estimating the amount of dark matter that actually exists there.
Researchers have been observing the galaxies around us for a long time now, what have noticed is that the expansion of the universe is not at an even rate, it is also not at even spread. The differences here are called peculiar velocities. For example our Milky Way galaxy is moving toward Andromeda at over 2 million kilometers per hour (that’s 1.24274e6 MPH)
The previous models of the universe have not complexly accounted for the motion, as the team are very interested in how these movements interlink with the mass of objects in the universe. As it is these motions that can determine how the distribution of matter around the universe, in their largest scales. As we think dark matter accounts for a large majority of the mass in the universe, as it is hypothesized form of matter as it does not reflect light or emit light and thus cannot be measured directly. So with this new map available it can provide the basis of our knowledge’s upon dark matter, as it allows us to see and measure the distribution of mass and its gravitational effects upon visible matter and light.
“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,” said Hudson. The next step here is to get a more detailed analysis of these movements of large areas of mass to determine more about the universe and dark matters existence.
Journal Reference:
Carrick, S. J. Turnbull, G. Lavaux, M. J. Hudson. Cosmological parameters from the comparison of peculiar velocities with predictions from the 2M density field. Monthly Notices of the Royal Astronomical Society, 2015; 450 (1): 317 DOI: 10.1093/mnras/stv547