Astronomers reach new frontiers of dark matter
Dark matter is the mysterious, invisible force preventing our stars from speeding away from each other. There is roughly 6 to 7 times more dark matter in the universe than ordinary light-emitting matter.
Work carried out by Dr. Catherine Heymans of the University of Edinburgh, Scotland, and Associate Professor Ludovic Van Waerbeke of the University of British Columbia, Vancouver, Canada presented the largest ever scale of mapped dark matter to the American Astronomers Society in Austin, Texas. The presentation is the product of analysing the images of 10 million galaxies in 4 different regions of the sky, at a distance of 1 billion light years.
The observations in the images (like the one above) show that dark matter in the Universe is distributed as a network of gigantic dense (white) and empty (dark) regions, where the largest white regions are about the size of an Earth moon on the sky.
Dr Catherine Heymans, a Lecturer in the University of Edinburgh’s School of Physics and Astronomy, said: “By analysing light from the distant Universe, we can learn about what it has travelled through on its journey to reach us. We hope that by mapping more dark matter than has been studied before, we are a step closer to understanding this material and its relationship with the galaxies in our Universe.”
Light emitted from 6 billion years ago (roughly half the age the universe is today) is bent and distorted as it travels through massive clumps of dark matter. A wide field-imaging camera MegaCam in Hawaii, under a project succinctly called Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) captured this light and collected images over a 5-year period.
Professor Ludovic Van Waerbeke, said: “It is fascinating to be able to ‘see’ the dark matter using space-time distortion. It gives us privileged access to this mysterious mass in the Universe which cannot be observed otherwise. Knowing how dark matter is distributed is the very first step towards understanding its nature and how it fits within our current knowledge of physics.”
This research was supported by the European Research Council, Natural Sciences and Engineering Research Council of Canada, the Canadian Institute for Advanced Research and the Canadian Astronomy Data Centre.
More images are available at: