Euclid Telescope Unveils Dozens of Ancient Quasars, Rewriting Early Universe History

The European Space Agency Euclid Space Telescope has just blown open our understanding of the universe's infancy, announcing the discovery of 31 new quasars from the cosmic dawn. Among these, two are the most ancient ever observed, shining brightly when the universe was a mere 670 million years old – about 5% of its current age – and sending their light across 13 billion light-years to reach us today. This monumental find, published in Astronomy & Astrophysics, more than doubles the known population of such early, super-luminous objects, offering an unprecedented look into how the first supermassive black holes and galaxies began to form. These newly observed quasars act like cosmic lighthouses, providing crucial clues about the 'Epoch of Reionization,' a pivotal time when the universe transitioned from a dark, neutral fog into the transparent, ionized state we see now. Before Euclid, finding even a handful of these incredibly distant and faint objects took decades of painstaking effort with ground-based telescopes. The Euclid mission, launched in 2023, leverages its wide field of view and infrared sensitivity to efficiently survey vast areas of the sky, allowing scientists like Daming Yang of Leiden University to capture fainter light from these ancient beacons and unravel mysteries surrounding the rapid growth of supermassive black holes. As Euclid continues its ambitious mission to map a third of the sky, astronomers expect even more breakthroughs. The detailed study of these ancient quasars will not only inform future observations by other advanced telescopes, like NASA upcoming Nancy Grace Roman Space Telescope, but also refine our cosmological models, particularly those concerning dark matter and dark energy. Scientists are eager to see how far back in time Euclid can push our observations, promising to deepen our understanding of the universe's fundamental building blocks and its accelerating expansion.