The study, which has combined images from the Hubble Space Telescope with spectroscopic observations from the GTC, has confirmed the existence of a new example of a gravitational lens, a phenomenon predicted by Albert Einstein's theory of General Relativity.
The study, which has combined images from the Hubble Space Telescope with spectroscopic observations from the GTC, has confirmed the existence of a new example of a gravitational lens, a phenomenon predicted by Albert Einstein's theory of General Relativity. In this case, the observed effect is due to the alteration caused by a galaxy that acts like a magnifying glass amplifying and distorting, in four separate images in the form of a cross, the light of another galaxy located 20,000 million light years away.
One of the most striking conclusions of Albert Einstein's theory of general relativity is that the trajectory of light curves in the presence of matter. This effect can be observed in the case of light emitted by a distant galaxy, when its light passes close to another galaxy on its way to the observer. The phenomenon is known as gravitational lensing, because it is comparable to the deviation of light rays by the classic glass lenses. Similarly, gravitational lenses act like magnifying glasses that change the size, shape, and intensity of the image of the distant object.
Depending on the degree of alignment of the two sources, multiple images of the distant source can be observed, such as four separate images in the form of a cross (hence the name "Einstein's cross"), rings, or arcs. It is in general extremely difficult to spot a gravitational lens, because the separation between the images produced by the lens is usually very small, requiring high-resolution images to see them. It was precisely analyzing Hubble Space Telescope high-resolution images that it was possible to locate an asterism that looked like a new example of Einstein cross.
Read more at Instituto de Astrofísica de Canarias - IAC
Image: The newly discovered Einstein Cross J2211-3050. An elliptical galaxy (the yellow object) is acting as a lens, producing the four blue objects (marked ABCD) that are the images of a galaxy about 3 times more distant. With GTC it was possible to isolate and disperse the light of objects ABC, demonstrating that they belong to the same light source. (Credit: Hubble Space Telescope Credit: Instituto de Astrofísica de Canarias)
