Hubble captures “Einstein’s ring”

A new image from the Hubble Space Telescope shows the astonishing “Einstein Ring” billions of light years from Earth – a phenomenon named after Albert Einstein, who predicted that gravity could bend light.

The round object in the center of an image released by the European Space Agency is actually three galaxies represented by seven, with four separate images of the most distant galaxies forming a visible ring around the other galaxies.

The most distant galaxy – a special type of extremely bright galaxy with a supermassive black hole at its center known as a quasar – is about 15 billion light years from Earth.

At such a great distance, it should be invisible to even the best space telescopes, but its light is bent by the two galaxies in the foreground, about 3 billion light years away, so its image appears to us in five separate places: four times in the ring and once in the center of the ring, although this can only be detected in the digital telescope data.

This rare phenomenon is named after Einstein, the physicist who predicted in 1911 that gravity would affect light just as it affects physical matter. Einstein proposed the idea as a test of his general theory of relativity in 1915, and in 1919 British astronomer Arthur Eddington confirmed the effect during a solar eclipse on Principe Island off the west coast. from Africa, noting that the stars near the eclipsed disk appeared out of place in part because their light was distorted by the sun’s gravity.

Telescopes in Einstein’s time were unable to detect other signs of the phenomenon. It was first seen by astronomers at Kate Summit Observatory in Arizona in 1979 as a twin quasar QSO 0957 + 561, which is a single quasar that looks like two here on Earth because its image is “gravitationally detected” by a closer but invisible galaxy. .

Since then, astronomers have discovered hundreds of Einstein rings, although the alignment of distant galaxies must be perfect and none of them can be seen without a large telescope. A common formation is Einstein’s Cross, in which the distant galaxy appears as four separate images around a galaxy closer to Earth, but the nearest galaxy is too faint to be seen.

Einstein’s rings and Einstein’s junctions are more than just a phenomenon – a gravitational lens allows astronomers to search far into the depths of the universe, and also reveals hidden details of lensed galaxies.

“Einstein’s rings and Einstein’s crosses are supposed to be proof that there is more matter in the nearest galaxies than it appears, and that probably means dark matter,” he said. said Ed Krupp, astronomer and director of the Griffith Observatory in Los Angeles. Its distribution can help shed light on the identity and distribution of dark matter and the relative geometry of the entire universe.

These gravitational lenses have also been used to spy on some of the most distant dwarf galaxies in the universe, which, being among the oldest galaxies, astronomers can tell astronomers more about the formation of galaxies; While the gravitational “microlens” – the light differences of individual stars – has been used to reveal the invisible presence of distant exoplanets, Krupp said in an email.