Fourteen galaxies | S. Dagnello; NSF/NRAO/AUI

Massive Cosmic Collision Challenges Theories of the Early Universe

Astronomers report witnessing the formation of a galaxy cluster — the largest type of gravity-bound structure in the universe. And it’s not what they expected.

An artist's impression of SPT2349-56 shows a group of interacting and merging galaxies in the early universe. | M. Kornmesser/ESO