Early Galaxies Reionized The Universe After The Big Bang
Like our own world history, the Universe had its own cycle of events. After the initial Big Bang (though 'Bang' is a confusing word, it may have been rather dull), there were no light sources in the Universe. Instead, 370,000 years after the Big Bang electrons and protons combined to form neutral hydrogen gas and released the radiation presently observed as the cosmic microwave background (CMB), so stars and galaxies formed in a kind of cosmic 'Dark Ages' (sans invading barbarians) but those early star-forming galaxies produced enough ultraviolet radiation to ionize most of…