University of Waterloo | Royal Astronomical Society | 2017 Apr 12
Waterloo researchers capture the first composite image of a dark matter bridge that confirms the universe is tied together with a cosmic web
[c]Researchers at the University of Waterloo have been able to capture the first composite image of a dark matter bridge that connects galaxies together.
Dark matter filaments (red) bridge the space between galaxies (white) on this
false colour map. Credit: S. Epps & M. Hudson / University of Waterloo[/c][hr][/hr]
The composite image, which combines a number of individual images, confirms predictions that galaxies across the universe are tied together through a cosmic web connected by dark matter that has until now remained unobservable. ...
As part of their research, Hudson and co-author Seth Epps ... used a technique called weak gravitational lensing. It's an effect that causes the images of distant galaxies to warp slightly under the influence of an unseen mass such as a planet, a black hole, or in this case, dark matter. The effect was measured in images from a multi-year sky survey at the Canada-France-Hawaii Telescope.
They combined lensing images from more than 23,000 galaxy pairs located 4.5 billion light-years away to create a composite image or map that shows the presence of dark matter between the two galaxies. Results show the dark matter filament bridge is strongest between systems less than 40 million light-years apart. ...
The Weak Lensing Masses of Filaments between Luminous Red Galaxies - Seth D. Epps, Michael J. Hudson