Euclid telescope’s first major data release maps more than 900 million galaxies

The European Space Agency (ESA) released the first major set of data from its Euclid space telescope on 12 November. It contains more than 900 million galaxies and is open to scientists around the world.

The release, called DR1-Foundation, covers about 13 months of observations, from spring 2024 to spring 2025. That is 1,900 square degrees of sky, or 14% of the area Euclid is due to survey during its six-year mission. The data amount to 1.7 million gigabytes.

What is in the data

Besides the galaxies, the catalogue holds about 15,000 strong gravitational lens candidates, where the gravity of massive objects bends the light of more distant galaxies, more than 60 million quasar candidates and spectra from more than 160 million sources.

“This major Euclid data release represents the largest space-based survey of its kind,” Carole Mundell, ESA’s director of science, said, as quoted by Physics World.

Why it matters

Euclid was launched in July 2023 and operates at the second Lagrange point, L2, about 1.5 million kilometres from Earth. Its task is to build the most accurate 3D map of the universe yet, to study dark matter and the dark energy that is accelerating the universe’s expansion. The full first data release is due in mid-2027.