Europe’s Euclid space telescope has detected a rare halo of bright light around a nearby galaxy, astronomers reported Monday.
The halo, known as an Einstein ring, encircles a galaxy 590 million light-years away, considered close by cosmic standards. A light-year is 5.8 trillion miles.
Astronomers have known about this galaxy for more than a century and so were surprised when Euclid revealed the bright glowing ring, reported in the journal Astronomy and Astrophysics.
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 billion light-years away.
Gravity distorted the light from this more distant galaxy, thus the name honoring 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 rocketed from Florida in 2023. NASA is taking part in its mission to detect dark energy and dark matter in the universe.