Euclid telescope finds 31 ancient quasars, two from universe's infancy

The European Space Agency's Euclid space telescope has discovered 31 of the oldest quasars ever documented, including two that are the most distant and ancient ever observed, astronomers reported.

According to NASA, the two record-breaking objects formed during the universe's first 670 million years, when the cosmos was only about 5% of its current age. Their light has taken roughly 13 billion light-years to reach Earth. Twelve of the 31 quasars date to the universe's first 770 million years.

A quasar occurs when immense amounts of gas and dust spiral into a supermassive black hole. Extreme gravitational and frictional forces heat that material to millions of degrees, releasing more light than all the stars in the galaxy combined. Such objects can shine hundreds to thousands of times more brightly than entire galaxies.

Why the find matters

The discovery, detailed in the journal Astronomy & Astrophysics and posted to the preprint server arXiv, is the initial result of Euclid's high-redshift quasar search. The team selected the objects from roughly 3,000 square degrees of sky surveyed during the first 1.5 years of the Euclid Wide Survey.

Finding quasars from the universe's earliest years is hard: few galaxies had grown large enough to host them, their light is faint, and it can be easily confused with starlight. Most previously known examples were exceptionally luminous objects that stood out because they were easier to detect, giving astronomers a skewed view of the early population.

"Euclid is a true game-changer," said Daming Yang of Leiden University in the Netherlands, lead author of the study, in an ESA release. "Before, we could only find a handful of the very brightest ancient quasars, but Euclid lets us search far more efficiently across huge areas of sky."

Yang said the discoveries could help explain how the first giant systems formed and grew so quickly, calling it "one of the greatest mysteries in astrophysics."

The mission, led by ESA with contributions from NASA, launched in 2023. Euclid is surveying billions of galaxies to study dark energy, and its results will help inform plans for NASA's forthcoming Nancy Grace Roman Space Telescope.