The map covers over 1300 square degrees of the entire sky and spans several billion light years in extent. Red regions have more dark matter than average, blue regions less dark matter. Image Credit: Chihway Chang of the Kavli Institute for Cosmological Physics at the University of Chicago, and the DES collaboration
Scientists have just released the most accurate map to date of the structure of dark matter in the Universe, supporting the theory that dark energy and dark matter make up most of the cosmos.
The results from this survey could help to provide answers to one of the most pressing questions of the Universe – why is space at an ever-increasing rate?
Crucially, these findings support the theory that about 4 per cent of the present Universe is ordinary matter and 26 per cent comes in the form of mysterious cold dark matter.
The remaining 70 per cent is in the form of an elusive dark energy, which is possibly causing the accelerating expansion of the universe.
Using data from the international Dark Energy Survey (DES), scientists are now also able to compare the structure of the current universe with it’s structure at the very beginning.
“The DES measurements support the simplest version of the dark matter/dark energy theory,” says Joe Zuntz, of the University of Edinburgh, who worked on the analysis.
Comparisons of the current structure of the Universe were made with data taken by the European Space Agency’s Planck observatory of the Cosmic Microwave Background Radiation – the first light left over after the Big Bang.
These new results draw from data collected during the DES’s first year of operation which covered one thirtieth of the sky – an area equal to 6,600 full moons.
“It is remarkable that dark energy is now measured so accurately by DES,” says Ofer Lahav of University College of London, chair of the DES UK Consortium.
“However, the nature of dark energy is still a big mystery.”
The results were made using gravitational lensing – a phenomenon where light from a distant object is warped due to the presence of a strong gravitational field.
Such a technique enabled the DES team to directly map the gravitational patterns of 26 million galaxies over billions of light years.
“Bringing maps of galaxies and dark matter together gives us a whole new way to understand how the dark side of the Universe behaves,” says Jack Elvin-Poole, a PhD student at the University of Manchester.