Astronomers dissect a gigantic black hole with the "Einstein Cross"

Astronomers have used the ESO's (European Southern Observatory's) Very Large Telescope, along with a double natural "magnifying glass" known as the "Einstein Cross", to scrutinize the inner parts of the disc around a supermassive black hole 10 billion light years away.

The "Einstein Cross", a famous cosmic mirage, is a cross-shaped configuration consisting of four images of a single very distant source.

The multiple images are a result of gravitational lensing by a foreground galaxy, an effect that was predicted by Albert Einstein as a consequence of his theory of general relativity.

The light source in the Einstein Cross is a quasar approximately ten billion light-years away, whereas the foreground lensing galaxy is ten times closer.

The light from the quasar is bent in its path and magnified by the gravitational field of the lensing galaxy.

This magnification effect, known as "macrolensing", in which a galaxy plays the role of a cosmic magnifying glass or a natural telescope, proves very useful in astronomy as it allows us to observe distant objects that would otherwise be too faint to explore using currently available telescopes.