New 3-D Map of Dark Matter Reveals Cosmic Scaffolding

This three-dimensional map offers a first look at the web-like large-scale distribution of dark matter, an invisible form of matter that accounts for most of the universe's mass. The map stretches halfway back in time to the beginning of the universe. The dark matter distribution was mapped with Hubble Space Telescope's largest ever survey of the universe, the Cosmic Evolution Survey ("COSMOS"). [Top] - Three slices through the evolving distribution of dark matter in the universe. [Bottom] - When the slices across the universe and back into time are combined, they make a three-dimensional map of dark matter in the universe. The three axes of the box correspond to sky position (in right ascension and declination), and distance from the Earth increasing from left to right (as measured by cosmological redshift). Note how the clumping of the dark matter becomes more pronounced, moving right to left across the volume map, from the early universe to the more recent universe. Credit: NASA, ESA, and R. Massey (California Institute of Technology)