Officially known as ACT-CL J0102-4915, the galaxy cluster has been nicknamed El Gordo. “This cluster is the most massive, the hottest, and gives off the most X-rays of any known cluster at this distance or beyond,” said Felipe Menanteau of Rutgers University. (Credit: X-ray: NASA/CXC/Rutgers/J.Hughes et al, Optical: ESO/VLT/Pontificia Universidad. Catolica de Chile/L.Infante & SOAR […]