For the first 300,000 years after the Big Bang the rapidly expanding universe was dark and filled with neutral hydrogen gas doing nothing much. But over the next half billion years the first stars and galaxies arrive through a process known as re-ionization – turning the lights on in the universe. Using an amazing Dark Energy Camera which is part of the -meter Blanco Telescope, at Cerro Tololo Inter-American Observatory (CTIO), in northern Chile, scientists have captured a picture of 23 of these young galaxies – the very dawn of visual time. Arizona State University astronomers Sangeeta Malhotra and James...