Euclid telescope discovers two oldest known quasars, each brighter than a trillion suns

The European Space Agency's Euclid space telescope has identified 31 previously unknown quasars from the universe's earliest chapter, including the two oldest ever detected, Live Science reports. The findings, published July 6 in Astronomy & Astrophysics, more than double the number of known quasars from that primordial era. The two most ancient quasars have redshifts of 7.77 and 7.69, meaning their light has traveled for more than 13 billion years and they shone just 670 million years after the Big Bang, when the universe was about 5% of its current age. Each outshines a trillion suns. Antonio La Marca, an ESA research fellow on the Euclid team, said the discoveries are a big step toward understanding how supermassive black holes grew so enormous so quickly after the Big Bang, one of cosmology's greatest mysteries. Daming Yang of Leiden University, first author of the study, said studying these early quasars helps understand how these enormous systems formed and grew so quickly. Euclid's wide-field survey is detecting fainter quasars across huge swaths of sky, changing a field previously limited to only the brightest examples.