New Galaxy Redshift Record

Subtle wisps of galaxies with a redshift around 10 have been detected from the Keck Observatory in Hawaii, claims a group of Caltech astronomers led by Richard Ellis. That high a redshift would mean looking back in time to when the universe was only 500 million years old. Ellis's team took advantage of strong gravitational lensing, conveniently provided by a galaxy cluster in the foreground, to search for boosted images in the background. They found six. Ultraviolet light from these ancient galaxies was probably what reionized (broke apart) the primordial hydrogen atoms in their region of space. The observation brings us closer to determining when the universe's first stars began to shine.