This picture of the galaxy cluster ACT-CL J0102−4915 combines images taken with ESO’s Very Large Telescope with images from the SOAR Telescope and X-ray observations from NASA’s Chandra X-ray Observatory. The X-ray image shows the hot gas in the cluster and is shown in blue. This newly discovered galaxy cluster has been nicknamed El Gordo — the "big" or "fat one" in Spanish. It consists of two separate galaxy subclusters colliding at several million kilometers per hour, and is so far away that its light has traveled for seven billion years to reach the Earth.
Photo credit: ESO/SOAR/NASA
Note: For more information, see El Gordo — A “Fat” Distant Galaxy Cluster. Also, see El Gordo (ACT-CL J0102-4915):
NASA's Chandra Finds Largest Galaxy Cluster in Early Universe.