Includes bibliographical references and index.

"Approximately 300,000 years after the Big Bang, all matter consisted of three chemical elements: hydrogen, helium, and a bit of lithium. This matter spread out as the universe expanded and cooled down, and from the far-flung gas clusters the first stars ignited. Eventually, due to gravitational clustering, primordial galaxies formed. The earliest galaxies, which evolved in the first few hundred million years after the Big Bang, contained stars that in turn contained only hydrogen and helium. These galaxies are thought to have produced copious amounts of ultraviolet radiation, which re-ionized the hydrogen in deep space and sparked one of the major phase transitions in the universe's early evolution, called the reionization era. In When Galaxies Were Born, Ellis describes efforts to reveal the oldest, most distant stars and galaxies in the universe and, in turn, to better understand the early evolution of the universe. Observational research into the largely uncharted cosmological era of "cosmic dawn" is notoriously difficult and involves such major space- and ground-based observatories as ESO's Very Large Telescope (VLT) and the Atacama Large Millimetre Array (ALMA) in Chile, the twin Keck telescopes on Mauna Kea in Hawaii, and the Hubble Space Telescope, and it will progress in the future using the Extremely Large Telescope (ELT) and Giant Magellan Telescope (GMT) in Chile, the Thirty-Meter Telescope (TMT) in Hawaii, and the NASA's James Webb Space Telescope (JWST), due to launch in mid-December 2021. While giving readers an inside look at the last several decades of progress in the field, Ellis also shares his own story and personal perspective, taking readers along as he uses observatories around the world to reveal how the first stars and galaxies came into being and how the earliest galaxies led to the further emergence of cosmic structure in the universe"--,Provided by publisher.

"One of today's leading astronomers takes readers inside the decades-long search for the first galaxies and the origin of starlight. Astronomers are like time travelers, scanning the night sky for the outermost galaxies that first came into being when our universe was a mere fraction of its present age. When Galaxies Were Born is Richard Ellis's firsthand account of how a pioneering generation of scientists harnessed the world's largest telescopes to decipher the history of the universe and witness cosmic dawn, the time when starlight first bathed the cosmos and galaxies emerged from darkness.In a remarkable career spanning more than forty years, Ellis has made some of the most spectacular discoveries in modern cosmology. He has traveled the world to conduct observations in locales as beautiful and remote as the Australian outback, the Canary Islands, Hawaii, and the Chilean desert. In this book, he brings to life a golden age of astronomy, describing the triumphs and the technical setbacks, the rivalries with competing teams, and the perennial challenge of cloudy nights. Ellis reveals the astonishing progress we have made in building ever larger and more powerful telescopes, and provides a tantalizing glimpse of cosmic dawn.Stunningly illustrated with a wealth of dramatic photos, When Galaxies Were Born is a bold scientific adventure enlivened by personal insights and anecdotes that enable readers to share in the thrill of discovery at the frontiers of astronomy"--,Provided by publisher.