Astronomers create largest map ever of dark matter

Science : Representing five years of work in imaging 10 million galaxies at distances of about 6 billion light-years, the new dark-matter map is 100 times larger than the largest one to date, writes Govert Schilling for Science. Although dark matter, which represents 98% of the mass of the universe, cannot be seen directly, it exerts a gravitational pull on normal matter, including light. By measuring that pull on starlight, astronomers were able to map its distribution. The new map shows that dark matter is concentrated in huge clumps and filaments, with large empty regions in between. Astrophysicist Ludovic Van Waerbeke of the University of British Columbia in Vancouver, Canada, and colleagues presented their results at the 219th meeting of the American Astronomical Society. Scientists hope that by plotting the distribution of dark matter throughout space, they will come closer to understanding what it is.