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A new Einstein Ring Discovered at the rims of our Outer Space

An Einstein ring is a distorted image of a very distant galaxy, which is termed “the source”. The distortion is produced by the bending of the light rays from the source due to a massive galaxy, termed “the lens”, lying between it and the observer. The strong gravitational field produced by the lens galaxy distorts the structure of space-time in its neighborhood, and this does not only attract objects which have a mass, but also bends the paths of light. When the two galaxies are exactly aligned, the image of the more distant galaxy is converted into an almost perfect circle which surrounds the lens galaxy. The irregularities in the circle are due to asymmetries in the source galaxy.

The "Canarias Einstein ring" is one of the most symmetrical discovered until now and is almost circular, showing that the two galaxies are almost perfectly aligned, with a separation on the sky of only 0.2 arcseconds. The source galaxy is 10,000 million light years away from us. Due to the expansion of the Universe, this distance was smaller when its light started on its journey to us, and has taken 8,500 million years to reach us. We observe it as it was then: a blue galaxy which is beginning to evolve, populated by young stars which are forming at a high rate.  The lens galaxy is nearer to us, 6,000 million light years away, and is more evolved. Its stars have almost stopped forming, and its population is old.

Recently, A new photograph from the Hubble Space Telescope shows a stunning “Einstein Ring” billions of light-years from Earth — a phenomenon named after Albert Einstein, who predicted that gravity could bend light. The round object at the center of the photograph released by the European Space Agency is actually three galaxies that appear as seven, with four separate images of the most distant galaxies forming a visible ring around the others. The farthest galaxy — a special type of very bright galaxy with a gigantic black hole at its center, known as a quasar — is about 15 billion light-years from Earth. Quasars are galaxies with supermassive black holes at their cores that gobble up enormous amounts of matter and blast out so much radiation that they're over a trillion times more luminous than the brightest stars. The light from the quasar has been bent around the galaxy pair because of their enormous mass, giving the incredible appearance that the galaxy pair are surrounded by four quasars — whereas in reality, a single quasar lies far beyond them, At such a great distance, it should be invisible to even the best space telescopes, but its light is curved by the two galaxies in front, about 3 billion light-years away, so its image appears to us in five separate places: four times in the ring and once at the center of the ring, although that can be detected only in the telescope’s numerical data. 

The 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 theory of general relativity in 1915, and in 1919 the British astronomer Arthur Eddington confirmed the effect during a solar eclipse on the island of Principe off the west coast of Africa, noting that stars near the eclipsed disk appeared fractionally out of place because their light was being bent by the sun’s gravity. Telescopes in Einstein’s time weren’t able to detect any other signs of the phenomenon. It was seen first by astronomers at the Kitt Peak Observatory in Arizona in 1979 as Twin Quasar QSO 0957+561, a single quasar that looks like two here on Earth because its image is “gravitationally lensed” by a closer but unseen galaxy.

Einstein Rings and Einstein Crosses are more than just pretty phenomena — gravitational lensing allows astronomers to look much farther into the depths of the universe, and it reveals otherwise hidden details of the galaxies that cause the lensing. The Einstein Rings and Einstein Crosses are presumably evidence of more material in the closer galaxies than meets the eye, and that most likely means dark matter, their distribution can help illuminate the identity and distribution of dark matter and the relativistic geometry of the whole universe. Such gravitational lenses have also spotted some of the most distant dwarf galaxies in the universe, which, being among the oldest, can tell astronomers more about galaxy formation, while gravitational “microlensing” — variations in the light from individual stars — has revealed the unseen presence of distant exoplanets. 

Words by - Vinuri Arambepola (Faculty of Agriculture)