The Euclid space telescope discovers the universe's oldest known quasars

On July 6, 2026, research published in Astronomy & Astrophysics detailed the discovery of 31 ancient quasars by the Euclid space telescope. Among these are two that represent the oldest such objects ever observed, dating back to an era when the universe was approximately 670 million years old. The findings provide a concrete new baseline for cosmologists studying the earliest stages of celestial development.

To place this timeline in perspective, 670 million years represents roughly five percent of the universe's current age. Quasars are the highly luminous cores of active galaxies, powered by supermassive black holes that are consuming vast amounts of surrounding material. Locating them at such an early epoch offers a direct observational record of how these massive structures formed shortly after the dawn of the universe.

Prior to this release, the known population of primordial quasars was constrained by the observational limits of previous instruments. Euclid's latest data more than doubles the established catalog of these ancient objects. Expanding the sample size is a functional necessity for astronomers, who require broad, reliable datasets to map the distribution and rapid evolution of early galaxies without relying on isolated anomalies.

The Euclid space telescope was designed specifically to survey large swaths of the sky, measuring the geometry of the universe to better understand its composition. By identifying so many highly redshifted quasars in a single published dataset, the instrument has demonstrated its capacity to rapidly locate rare cosmological targets that ground-based observatories and narrower space telescopes frequently miss.

These findings establish a firmer empirical foundation for the study of the universe's infancy. With a significantly expanded population of early supermassive black holes now documented and verified, researchers have the necessary structural data to test and refine current models of early galaxy formation.