... Tonight's Sky . ... Gravitational wave search provides insights into galaxy evolution and mergers . ... galaxies . ... Explosion of galaxy formation lit up early universe . ... New data from the South Pole Telescope indicates that the birth of the first massive galaxies that lit up the early universe was an explosive event, happening faster and ending sooner than suspected. ... The data provide new constraints on the universeт??s first era of galaxy formation, called the Epoch of Reionization. ...