In cosmology, the is the era roughly 50 million to 1 billion years after the Big Bang when the first light-producing objects began to illuminate the universe.
: Gravity pulled primordial gas together to form the very first celestial structures, which eventually triggered the Epoch of Reionization by ionizing the surrounding gas. Cosmic Dawn
: Scientists use tools like the James Webb Space Telescope (JWST) and low-frequency radio telescopes to peer back over 13 billion years to witness these "first lights". In cosmology, the is the era roughly 50
: It marks the end of the "Cosmic Dark Ages," a time when the universe was filled only with neutral hydrogen and helium gas. : It marks the end of the "Cosmic
"Cosmic Dawn" most commonly refers to the when the first stars and galaxies formed , but it is also the title of a major NASA documentary and a sci-fi thriller film . 1. The Astronomical Phenomenon