An international team of astronomers has discovered the most distant progenitor to a galaxy supercluster ever. The discovery supports existing theories of how galaxy clusters evolve, and reveals how they are connected to the larger cosmic web. The study relies largely on data from the ODIN survey, conducted with the U.S. Department of Energy-fabricated Dark Energy Camera on the U.S. National Science Foundation Víctor M. Blanco 4-meter Telescope in Chile.

Galaxy clusters are the most massive gravitationally bound structures in the Universe. These colossal groupings of hundreds to thousands of galaxies span millions of light-years. They are held together by large concentrations of dark matter, which serves as the building block for the larger structure of the Universe.

Clusters that scientists observe relatively near to us in space and time are mature structures that evolved from what are known as ‘protoclusters.’ These protoclusters are enormous, loosely bound collections of galaxies that are in the process of merging together but have yet to settle into a stable cluster. By studying very distant protoclusters that formed when the Universe was relatively young, scientists can understand how modern galaxy clusters grew and evolved over time.