Free Astronomy Magazine September-October 2026

4 ASTRO PUBLISHING ing results. The telescope has now discovered an unprecedented num- ber of 31 new quasars in the early Universe, pushing back to a time when the cosmos was just 5% of its current age. “These early quasars date back to the Universe’s infancy,” says Daming Yang of Leiden University in the Netherlands, lead author of the Eu- clid discovery paper. “By finding and studying them, we can better un- derstand how these enormous sys- tems formed and grew so quickly – one of the greatest mysteries in as- trophysics.” The earliest quasars we knew of until now were just the tip of the iceberg: the rare and bright outliers that have been easiest to spot. We simply hadn’t found enough quasars from the Universe’s early days to study them properly as a group. Euclid’s new finding changes all that, capturing not just the bright outliers but most of the an- cient quasar population. SEPTEMBER-OCTOBER 2026 Euclid discovers the most ancient quasar in the Universe by ESA Q uasars represent a brief phase in a galaxy’s life dur- ing which large amounts of material spiral into the central su- permassive black hole, releasing enormous amounts of energy. In this phase, the galaxy’s nucleus shines more brightly than anything else in the Universe, often outshin- ing the rest of its host galaxy by hundreds to thousands of times. We’ve been hunting for the Uni- verse’s very first quasars for decades. These objects reveal what was hap- pening during the earliest days of the cosmos, including how the first supermassive black holes and galax- ies took shape. However, quasars from this time are difficult to find. They’re rare, as few galaxies had yet had time to grow big enough, and their primordial light is both faint and easy to confuse with that from stars lying closer to us. Euclid, launched in 2023, is digging deeper into this mystifying part of ancient cosmic history – with excit-