Overview
- The Euclid team published their results on Monday, July 6, reporting spectroscopic confirmation of 31 quasars at redshifts 6.6–7.8 and two new highest-redshift objects at z = 7.77 and z = 7.69.
- Euclid's wide-field near-infrared imaging was paired with machine-learning selection and ground-based spectroscopy from Keck, Magellan and the Large Binocular Telescope to separate faint high-redshift quasars from look-alike stars and measure their distances.
- The new sample more than doubles the number of known quasars beyond redshift 7 and includes fainter, more typical objects rather than only the brightest outliers, enabling statistical studies of early black-hole growth.
- The finds sharpen a core puzzle: how black holes reached hundreds of millions to billions of solar masses so quickly, and the team has approved follow-up programs with JWST, ALMA and other telescopes to measure black-hole masses, host-galaxy properties and the impact on reionization.
- Euclid will continue its six-year sky survey with a major data release planned for late 2026 that the team says should reveal many more high-redshift quasars and push searches beyond redshift 8.