Europe's Euclid space telescope captures rare 'Einstein ring' of light in nearby galaxy

Europe's Euclid space telescope has detected a rare ring of bright light around a nearby galaxy, astronomers have said.

The halo, known as an "Einstein ring," encircles a galaxy 590 million light-years away, considered close by cosmic standards.

Astronomers have known about this galaxy for more than a century and so were surprised when Euclid revealed the bright glowing ring which was reported in the journal Astronomy and Astrophysics.

"I find it very intriguing that this ring was observed within a well-known galaxy, which was first discovered in 1884," Valeria Pettorino, the Euclid project scientist at the European Space Agency (ESA), said in a statement.

"The galaxy has been known to astronomers for a very long time. And yet this ring was never observed before," she added.

"This demonstrates how powerful Euclid is, finding new things even in places we thought we knew well".

Euclid's six-year mission

An Einstein ring is light from a much more distant galaxy that bends in such a way as to perfectly encircle a closer object, in this case, a well-known galaxy in the constellation Draco.

The faraway galaxy creating the ring is more than 4.4 billion light-years away.

Gravity distorted the light from this more distant galaxy, thus the name honouring Albert Einstein. The process is known as gravitational lensing.

"All strong lenses are special, because they’re so rare, and they’re incredibly useful scientifically. This one is particularly special, because it’s so close to Earth and the alignment makes it very beautiful," lead author Conor O’Riordan of Germany’s Max Planck Institute for Astrophysics said in a statement.

Euclid was launched on a six-year mission from Florida to explore the dark universe in July 2023.

According to ESA, the telescope will map a third of the sky and observe billions of galaxies.