During this dark age, there was no light-based signal we can study —”there was no visible light” said University of Washington professor of physics, Miguel Morales, about the dark age, the starless era, a gap of several hundred million years following the Big Bang devoid of data, when elementary particles combined to form hydrogen but no stars or galaxies existed yet to light up the Universe.
Thirteen billion years ago our universe was dark. There were neither stars nor galaxies; there was only hydrogen gas left over after the Big Bang. Eventually hydrogen atoms began to clump together to form stars—the very first ones to exist—initiating a major phase in the evolution of the universe, known as the Epoch of Reionization, or EoR.
“The first light of the universe might imply the existence of an important population of more exotic objects like faint quasars, X-ray binary stars, or perhaps even decaying/annihilating particles.” —Harvard-Smithsonian Center for Astrophysics
