Galactic zoo

Europe's Euclid space telescope, which is on a mission to shed light on the mysteries of dark matter and dark energy, has released its first data with a little help from volunteers and AI.

The telescope launched in 2023, aiming to chart one third of the sky - encompassing 1.5 billion galaxies - to create what has been billed as humanity's most accurate 3D map of the universe.

Euclid, which is now hovering 1.5 million kilometers from Earth, has previously released images of a range of strange galaxies, colorful nebulas and shining stars.

But the first release of astronomical data is "a new milestone for our dark universe detective," the European Space Agency's science director Carole Mundell said.

The huge amount of data - which was accompanied by 27 scientific papers - still only covers less then 0.5 percent of the sky that Euclid will scan over its six-year mission.

Yet the early data already offers hints about the overall structure of the universe known as the "cosmic web," project scientist Valeria Pettorino said.

Between large empty spaces, there are massive clusters of galaxies connected by filaments of material which make up this web, she said.

This unimaginably massive structure cannot be explained by visible matter alone, so scientists believe dark matter and dark energy must play a role. These invisible forces are thought to make up 95 percent of the universe yet remain shrouded in mystery.

Dark matter is believed to be the glue that holds galaxies together, while dark energy pulls them apart by making the universe expand faster and faster over time.

Because looking into distant space also means looking back in time, Euclid allows scientists to track this cosmic tussle over most of the history of the universe - and hopefully discover more about their true nature.

"Ultimately, we want to test the laws of gravity," Mundell said.

Einstein's theory of relativity has passed every test thrown at it, "but it does not yet, in its current form, explain the accelerated expansion of the universe," which is driven by dark energy, she explained.

AGENCE FRANCE-PRESSE