Astronomy Cast Ep. 665: The Age of Reionization by Fraser Cain & Dr. Pamela Gay The Cosmic Microwave Background Radiation tells us so much about the Universe. After that era, the Universe went dark. Then, as gas pulled together into the first stars and eventually galaxies, light returned, beginning the Age of Reionization.   This video was made possible by the following Patreon members: Burry Gowen Stephen Veit Jordan Young Jeanette Wink Kevin Lyle Venkatesh Chary Andrew Poelstra Brian Cagle David Truog Gerhard Schwarzer THANK YOU! - Fraser and Dr. Pamela