Scientists took four pictures of an exploding supernova (supernova), because the star was hidden behind massive clusters of galaxies, which bent light and time, creating a gravitational magnifying glass. NASA defines a supernova as the explosive explosion of a star. This is the biggest space explosion. The Hubble Space Telescope image of an Einstein Cross shows how the supernova’s light is split into four images. (arrows in box). Patrick Kelly, University of California Berkeley Postdoctoral Scholar, has discovered that one of the lenses – a large galaxy in a cluster of galaxies, which both are gravitationally bending light and magnifying it – project four images of a distant supernova. Gravitational Lensing Gravitational lenses is when light coming from distant objects is distorted around an object like a huge galaxy. Einstein’s Theory of General Relativity predicted gravititational lensing. The Universe’s largest structure is galaxy clusters. They are so strong that their gravitational force can warp spacetime around them. Scientists will have a rare opportunity to examine a distant supernova as well as the distribution of dark matter within the cluster and lensing galaxy. Kelly was looking at HST (HubbleSpace Telescope) images on November th, 2014, and saw the supernova. He said that they could see it four times, and then measure how long the delays are between each image. This will allow them to learn more about the supernova, the star from which it came, and also about gravitational lenses. It will be interesting.” Kelly is part of the GLASS team (Grism Lens Amplified Survey From Space), which was led by UCLA’s Tommaso Treu. This team has collaborated with the FrontierSN team, organized by Steve Rodney at Johns Hopkins University, to search for distant supernovae. Illustration showing how gravitational lensing, which is the process of magnifying the supernova’s light behind it in a huge galaxy cluster, bends and focuses that light. This results in multiple photos of the Einstein Cross, the star that is exploding. Image: UC Berkeley. A 50-year Search Professor Alex Filippenko of Kelly’s team said that it was a remarkable discovery. For 50 many years we have been looking for supernovae with strong lensing. Now, we’re happy to announce that one has been found. It is not only cool but it also should give a lot of important astrophysical information.” Astronomers have the opportunity to watch the supernova’s replay over the next ten year. Because light is distorted by a gravitational lens and arrives on earth in different time periods, it causes this effect. Computer modelling shows this lensing cluster that although astronomers did not observe the supernova 50 or 10 many years ago, they will again be able see it within the next ten year. Professor Filippenko stated that the “longer the path or stronger the gravitational fields through which light moves, then the longer the delay.” This supernova was reported by Dr. Kelly, along with colleagues, in Science’s special March 6th edition (citation below), to mark the 100th anniversary of Albert Einstein’s General Theory of Relativity. The supernova distant has been named SN Refsdal in honor of Sjur Refsdal (1935-2009),, a Norwegian astrophysicist best known for pioneering gravitational lensing. It is located 9.3 billion light-years from Earth (redshift =1.5), near the edge of our observable Universe. About 5 billion light-years from Earth is the massive galaxy responsible for gravitational lensing (redshift = 1.5). Einstein Cross, Einstein Lens Einstein’s General Theory of Relativity states that densely populated areas of matter in the Universe have a lens effect on light. This bends the light and magnifies objects. It was discovered by 1979 in the SBS 0957+561 Twin Quasar, and has given us a glimpse into the beginning of our Universe’s history 13.8billion years ago. Kelly stated that gravitational lenses can be compared to magnifying glasses. This is like having an even bigger telescope. These galaxy clusters can give us magnifications up to 100. If the path of the light passes far away from the massive mass that bends timetime or is not particularly large, weak lensing will result, which slightly distorts the background object. If the background object lies close to the mass, however, then strong lensing may cause the galaxy cluster or lensing galaxy to become an “Einstein Ring”. A strong lensing of small, pointy objects can produce an “Einstein Cross”, which is a result of the use of weaker lenses. Multiple images arranged around the lens. Professor Filippenko stated that while we have witnessed many distant quasars as Einstein crosses before, this was the first observation of a supernova in such a way. ” Pat Kelly carefully studied the HST data to discover this unusual pattern. “Luck comes to those who are ready to receive it.” This galaxy is part of the massive MACS J 6 +2223, cluster that scientists have been studying for more than ten years. 2009 reported that the cluster produced the most detailed image ever of a spiral galaxy through a gravitational lens. The newly discovered exploding star can be found in the galaxy’s spiral arms. It also appears on multiple images surrounding the lensing cluster. However, the red elliptical cluster within it splits up the exploding star into four images. Kelly stated that although strong lensing is possible from a red galaxie, the galaxy in question is part of an extended cluster, magnifying it even more. This is why we have a dual lensing system. Dr. Kelly, along with his colleagues, examined older HST images. They saw the supernova faintly in November 3, 7 days earlier. HST has taken several dozen images so far of the supernova with the Wide Field Camera 3 infrared camera. This is part of the Grism Study. HST Astronomers intend to take more photos and spectra of supernovas as HST continues its focus on that region for six months. Kelly stated that “By chance, we were able to track it very closely in all 4 images, getting data every 2 to 3 days.”
