Six galaxies caught mid-merger 1.2 billion years after the Big Bang

A team led by Ronaldo Laishram (National Astronomical Observatory of Japan) has used deep JWST imaging and slitless spectroscopy from the SAPPHIRES survey to identify SCGG-z5: six galaxies at z ≈ 4.97 confined to a patch just 52,000 light-years across, caught in the act of merging into what may become a future cluster's brightest galaxy.