Many of the oldest and most massive galaxies reside together in enormous structures known as clusters, and now a team of astronomers has confirmed the existence of an unusually distant galaxy cluster – a group of 19 galaxies located at precisely the same distance of 9.9 billion light years.
New research from a team led by Andrew Newman from Carnegie’s Institution for Science in Washington, D.C., has confirmed the presence of an unusually distant galaxy cluster, JKCS 041.
“Our observations make this galaxy cluster one of the best-studied structures from the early universe,” Newman said.
In research appearing in The Astrophysical Journal, Andrew Newman of the Carnegie Institution for Science and his colleagues explain how they used the Hubble Space Telescope to capture images of the distant cluster JKCS 041. While they have been studying the cluster since 2006, these new observations allowed them to finally confirm its distance.
The study authors took the images of JKCS 041 and used a technique known as spectroscopy to split the starlight from the galaxies into its constituent colors. In a statement, Newman explained that the observations made as part of their research “make this galaxy cluster one of the best-studied structures from the early universe.”
“Because JKCS 041 is the most-distant known cluster of its size, it gives us a unique opportunity to study these old galaxies in detail and better understand their origins,” explained Newman.
Massive galaxies continue expanding in overall size after becoming quiescent. It is believed that this occurs as galaxies collide with one another, forming a new, larger galaxy. Early clusters are believed to be excellent locations for these collisions to take place. However, Newman and his colleagues discovered that the galaxies in JKCS 041 were actually growing at almost the same rate as non-cluster galaxies.