An unusual cosmic event was captured by the physicists of the University of California who used the Hubble Space Telescope to observe the universe. They saw what one could label as four simultaneous supernovae.
A study published in Science explains what the astronomers actually saw. The spectacular image was presented four different perspectives of the same supernova. A supernova observed from four different angels.
How was that possible? Such an interesting observation could be made due to a cosmic phenomenon called gravitational lens. Even if Orest Chwolson and Frantisek Klin discussed the problem of gravitational lens, the discovery of this phenomenon is associated with Albert Einstein, who published a paper about it in 1936.
Even if we have incredible telescopes, the tremendous distances between cosmic objects in our universe make it impossible for our scientists to observe everything. This is where gravitational lens comes in.
Light is bent by the massive forces of gravity, causing what they call a magnifying lens. They are all around the universe. The gravitational forces of nearby galaxies or clusters of galaxies in a way that makes it possible for scientists to see things they wouldn`t normally have the chance to see.
“You can think of these time-variable source images of the supernova as trains. Each leaves the station at the same time but arrives at different times because the ‘routes’ and the ‘landscape’ they travel through are not the same.”,
said Kasper Schmidt, who is co-author of the study and a researcher at the University of California.
This is the case of the supernova, which is located 9.3 billion light years away from Earth, at the outskirts of our observable universe. The scientists say it was a lucky occurrence that they were able to see the supernova. Without the unusual lensing, the light from the supernova may have never reached Earth. A cluster of galaxies bent the light and was responsible for three out of four images and the fourth image was produced by another galaxy. Finally, the light of the supernova was amplified by 20 times.
Curtis McCully, who is co-author of the study published by Science, said that the image they saw by Hubble allows them to calculate the difference between the size of the universe 5 million years ago to the size the universe is nowadays. Thus, they can measure how fast the universe is expanding.
Still, the scientists added that it will take time until they will come up with these results.
Image Source: Nature World News