Astronomers say the light from the supercluster has traveled for over 12 billion years to reach telescopes on Earth. It might be one of the earliest large clusters of galaxies in the universe because it is so old. One of the most active star-forming proto-clusters is located there.

The South Pole Telescope found a supercluster in the sub millimeter band. One of the team members who conducted follow-up observations with the telescopes was an astronomer from the Harvard Smithsonian Center for Astrophysics.

The South Pole Telescope (SPT) is a 10-meter-diameter telescope located at the Amundsen-Scott South Pole Station, Antarctica. In addition to its primary mission of measuring the cosmic microwave background, the SPT is part of the Event Horizon Telescope project. Credit: Daniel Luong-Van

Dozens of other star-forming galaxies, as well as over thirty sub millimeter-bright ones, can be found in SPT2349?56 Even though this is a cluster of galaxies from the early Universe, active star formation is taking place at an incredible rate. One of the best sources is the merger of over twenty galaxies.

The team was unsuccessful in trying to get the stellar mass of the system. It was not possible to know whether the huge burst of stars they observed was the result of an efficient system or simply arose because the system was so large.

A typical supercluster is made up of all the groups and clusters that seem to be related by mutual attraction. There are 130 superclusters located within the 1.3 billion light-year range of the Milky Way. The South Pole Telescope detected a supercluster from the early Universe that weighed in at 800 trillion Suns.

The astronomer found that the star formation rate in this primordial cluster is comparable to the star formation rate in nearby, regular galaxies, and so they conclude that the star formation processes at work in this early Universe are similar to those that came later. The activity is nearing the end of this tumultuous phase as the raw material for stars is being dissipated.

The core galaxies of this supercluster are predicted to merge quickly into one of the brighter clusters, according to the astronomer.

A false-color image of the far-infrared emission from a massive protocluster of galaxies (in the circle) dating from the epoch about 1.4 billion years after the big bang. Astronomers have completed deep optical and infrared observations of the complex and concluded that the star formation processes at work, although exceptionally active, generally seem to follow the same processes seen in our galaxy. Credit: NASA/ESA/Herschel; Miller et al.

The paper is in Oxford Academic Monthly Notes.