https://www.ipac.caltech.edu/news/new-j ... n-frontier
A stunningly concentrated and hefty galaxy cluster, from a time in the universe’s history when such massive structures aren’t expected to have fully formed yet, is challenging cosmic evolution theories
team led by researchers from IPAC have revealed that the cluster is the most distant example of strong gravitational lensing with a galaxy cluster.
When astronomers first laid eyes on this galaxy cluster dubbed XLSSC 122, they knew they had found something special. The cluster appeared highly evolved despite being more than 10 billion light-years away, back in an era when other galaxy groupings had only just started to come together.