Euclid and Keck Double the Earliest Quasars and Set a Distance Record
Euclid found 12 new quasars beyond redshift 7, more than doubling the known number, including two record holders at redshifts 7.77 and 7.69.
ESA’s Euclid space telescope and the W. M. Keck Observatory have more than doubled the number of known quasars from the universe’s first 770 million years, and set a new distance record. The study, led by Daming Yang of Leiden University, is in Astronomy & Astrophysics, and Keck announced it on July 6, 2026.
A quasar is the brilliant center of a galaxy powered by a supermassive black hole feeding on gas, a kind of object first identified by Maarten Schmidt in 1963. The team selected 31 quasar candidates from Euclid’s Wide Survey, part of a mission designed to map dark matter and dark energy. Keck confirmed 21 of them using its MOSFIRE, LRIS and KCWI instruments. Euclid has found 12 new quasars above redshift 7. Redshift measures how much the universe has stretched light since it left its source; above 7 means the light set out in the first 770 million years. Before Euclid, only a handful of quasars that distant were known.
The two most distant, EUCL J172902.75+641018.1 and EUCL J125308.55+705432.3, have redshifts of 7.77 and 7.69, a new record. Both shone within the universe’s first 670 million years.
Why it matters: building a black hole of millions or billions of solar masses that fast is hard to explain. A handful of examples could be flukes; a real sample lets astronomers test how supermassive black holes grew so large so quickly after the Big Bang. More in our black holes guide and guide to galaxies.
What to watch next: as the Euclid Wide Survey continues, the sample of early quasars should keep growing.
Primary source
This summary is based on W. M. Keck Observatory and the peer-reviewed paper. Read the original for full details, data and caveats.
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