A splatter of red, denoting galaxies, lies at the center of this image and extends toward the lower left. This is the remnant of a cosmic collision. Eons ago, one group of galaxies plunged into another at millions of miles per hour, leaving a wreckage in its wake. The galaxy cluster El Gordo is all that remains of this raucous event.
The Dark Energy Survey has posted this detailed image of the Fornax galaxy cluster. The survey will measure the distributions of galaxies that are far away from Earth and compare them to the patterns of galaxies closer to Earth. Differences in these patterns give indispensable clues about how dark energy has affected spacetime over the last several billions of years.