Astronomers working with the Hubble telescope have published a new image. It shows stars, distant galaxies, and a bizarre cosmic mirage known as the Einstein ring.
The Hubble image shows a tiny section of sky in the southern constellation Hydra. The closest objects to us in the photo are stars located in our Milky Way galaxy. They can be recognized by diffraction rays. This is a characteristic optical effect that occurs due to the design of the telescope.
For example, the bright star at the very edge of the prominent bluish galaxy LEDA 803211 at the bottom of the frame is 3,230 light-years away from Earth. For comparison, the galaxy itself is 622 million light years away from us. By human standards, this is an unimaginably vast distance. But for Hubble, it’s a relatively close object, so we can see various details of the structure. In the photo, you can see the bright galactic nucleus as well as numerous star clusters scattered along its spiral arms.
The image also shows many more distant galaxies. They look star-shaped, but unlike real stars, they have no diffraction rays. Among all of them, one pair particularly stands out: a smooth golden galaxy surrounded by a nearly complete ring in the upper right corner of the image. This curious configuration is an optical mirage formed by a gravitational lensing event. It occurs when light from a more distant object is distorted and magnified by the gravity of a massive foreground object, such as a galaxy or cluster of galaxies. Albert Einstein once predicted such curvature of spacetime in his General Theory of Relativity. This is why they are often called Einstein rings.
The lensed galaxy whose image turned into a ring is incredibly far from Earth: we see it as it was when the universe was only 2.5 billion years old. Astronomers actively use gravitational lenses in their work. They provide them with the opportunity to see incredibly distant objects that even the most powerful telescope in existence could not observe under normal circumstances.
According to Esahubble
