Astronomers find the most distant supernova ever seen: 10.5 billion light-years away

Astronomers have discovered the most distant supernova yet, at a distance of 10.5 billion light-years from Earth. The supernova, called DES16C2nm, is a catastrophic explosion that marked the end of a massive star about 10.5 billion years ago. Only now does the light come to us. The team of astronomers behind the discovery have published their results in a new paper available on arXiv.

The supernova was discovered by astronomers involved in the Dark Energy Survey (DES), a collaboration of astronomers in different countries. DES’s job is to map several hundred million galaxies to help us discover more about dark energy. Dark Energy is the mysterious force that we believe is causing the accelerated expansion of the Universe.

DES16C2nm was first detected in August 2016. Its distance and extreme brightness were confirmed in October of that year with three of our most powerful telescopes: the Very Large Telescope and the Magellan Telescope in Chile, and the Keck Observatory in Hawaii.

DES16C2nm is what is known as a superluminous supernova (SLSN), a type of supernova discovered only 10 years ago. SLSNs are the rarest and brightest type of supernova known to us. After the supernova exploded, it left behind a neutron star, which is the densest type of object in the universe. The extreme brightness of SLSNs, which can be 100 times brighter than other supernovae, is thought to be caused by material falling onto the neutron star.

Lead author of the study, Dr Mathew Smith, from the University of Southampton, said: “It’s exciting to be part of the survey that has discovered the oldest known supernova. DES16C2nm is extremely distant, extremely bright and extremely rare, not the kind of thing you run into every day as an astronomer.”

Dr. Smith went on to say that the discovery is not just exciting just because it is so distant, ancient and rare. He also provides insight into the cause of SLSNs: “The ultraviolet light from the SLSN tells us about the amount of metal produced in the explosion and the temperature of the explosion itself, both of which are key to understanding what causes and drives these cosmic explosions.” . ”

Now that the international team behind the Dark Energy Survey has found one of the SLSNs, they want to find more. Co-author Mark Sullivan, also from the University of Southampton, said: “Finding more distant events, to determine the range and total number of these events, is the next step. Now that we know how to find these objects at even greater distances, we are actively looking for more of them as part of the Dark Energy Survey.”

The instrument used by DES is the newly built Dark Energy Camera (DECam), which is mounted on the 4-meter Victor M. Blanco Telescope at the Cerro Tololo Inter-American Observatory (CTIO) in the Chilean Andes. DECam is an extremely sensitive 570 megapixel digital camera designed and built just for the Dark Energy Survey.

The Dark Energy Survey involves more than 400 scientists from more than 40 international institutions. It began in 2013 and will conclude its five-year mission sometime in 2018. DES is using 525 observing nights to conduct a deep wide-area survey to record information from 300 million galaxies that are billions of years apart. distance light. Land. DES is designed to help us answer a burning question.

According to Einstein’s General Theory of Relativity, gravity should be causing the expansion of the universe to slow down. And we thought it was, until 1998, when astronomers studying distant supernovae discovered that the opposite was true. For some reason, the expansion is accelerating. There are really only two ways to explain this. Either the General Relativity theory needs to be superseded, or a large part of the universe, about 70%, consists of something exotic that we call Dark Energy. And this Dark Energy exerts a force opposite to the attractive force exerted by “normal” matter, causing the expansion of the universe to accelerate.