While the “Epoch of Reionization” sounds like the title of a sci-fi novel destined for a Hugo award, this very real era of the universe featured the first light from the very first stars. Before this epoch, the universe was nothing more than a dark void filled with a fog of primordial hydrogen gas—and then, suddenly, there was light. For decades, scientists have searched for a source of radiation powerful enough to have cleared away this fog and introduced light into the universe. Now, an international team of scientists have analyzed the first faintest galaxies ...
