‘El Gordo’ is Largest Distant Galaxy Cluster Ever Seen
Galaxy clusters are the largest stable structures in our Universe. Seven billion light years away and with two million billion times the mass of our Sun, a cluster nicknamed “El Gordo” – “the Fat One” in Spanish – has been spotted and is said to be currently undergoing a merger and growing even larger.
Galaxy clusters yield many cosmic superlatives; mergers such as the one that El Gordo appears to be undergoing are the most energetic events in the Universe, as vast amounts of matter – and the mysterious dark matter – crash into each other at breakneck speeds. Mapping out the process of cluster growth will be critical to understand the interplay between the forces of dark matter and dark energy.