Einstein ring spotted around galaxy a ‘mere’ 500 million light years away
The discovery can help scientists test Albert Einstein’s general theory of relativity.
Scientists have found a rare Einstein ring in “our cosmic backyard” using images from the Euclid space telescope.
The discovery, published in the journal Astronomy And Astrophysics, is of a circle of light created by gravitational lensing around a galaxy 500 million light years away called NGC 6505.
This ring is made up of light from a galaxy 4.42 billion light years away and what can be seen from Earth is distorted by gravity.
Professor Thomas Collett, from the University of Portsmouth’s Institute of Cosmology and Gravitation, said such rings can help scientists test Albert Einstein’s general theory of relativity.
He said: “This lens is particularly special because it’s in our cosmic backyard: a ‘mere’ 500 million light years away.
“In fact, it’s so close that astronomers first observed the galaxy in the 1880s, but only with the resolving power of Euclid can we now reveal that it’s a gravitational lens.
“Nearby lenses are exciting because they allow us to test the validity of general relativity on astronomical scales.”
It allows astronomers to see the light from distant galaxies that would otherwise be hidden.
Conor O’Riordan, of the Max Planck Institute for Astrophysics in Germany and lead author of the first scientific paper analysing the ring, said: “An Einstein ring is an example of strong 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.”
Launched in July 2023, the Euclid mission aims to create a 3D map of the universe by observing two billion galaxies, which will help scientists understand its cosmic history.