Huge 10.5-billion-year-old Cosmic Explosion Is the Most Distant Supernova Ever Discovered

Astronomers have confirmed that a huge cosmic explosion—which took place 10.5 billion years ago—is the most distant supernova ever detected.

When massive stars come to the end of their life cycles, they self-destruct in a cataclysmic final explosion known as a supernova. However, the exploding star described in the new findings—referred to as DES162nm—is part of an extremely rare and bright class of events known as super-luminous supernovae (SLSN).

These events—which are 10 or more times more powerful than normal supernovae—can be produced by several different mechanisms.

In the case of DES162nm, it is thought the event was caused by vas quantities of material falling into a rapidly rotating neutron star – one of the densest objects in the Universe—which was formed in the aftermath of a massive explosion.

DES162nm emitted vast quantities of light, which has taken 10.5 billion years to reach us here on Earth. This length of time is around three quarters the age of the Universe.

Lead author of the study Mathew Smith, from the University of Southampton, told Newsweek that the explosion "is 230 million-years older than the previous record holder", meaning it is also 230 million-light-years more distant from Earth. In addition, it is "100 times brighter than a normal type 1a supernova".

Read more: 'Zombie star' has been exploding for years and will not die

DES162nm was first spotted in August 2016 using the Cerro Tololo Inter-American Observatory in Chile. The investigations were part of an international collaboration involving more than 400 scientists known as the Dark Energy Survey—a project designed to map hundreds of millions of galaxies in a search for the mysterious force that is thought to be behind the accelerating expansion of the universe.

DES162nm's extreme distance and brightness were identified two months later with the help of three of the world's most powerful telescopes—the Keck Observatory in Hawaii, as well as the Very Large Telescope and Giant Magellan Telescope, both based in Chile. The findings have now been described in a new study, published in the Astrophysical Journal.

Supernova
Illustration of a supernova. NASA

"It's thrilling to be part of the survey that has discovered the oldest known supernova", lead author Mathew Smith, from the University of Southampton, said in a statement. "DES16C2nm is extremely distant, extremely bright, and extremely rare—not the sort of thing you stumble across every day as an astronomer."

"As well as being a very exciting discovery in its own right, the extreme distance of DES16C2nm gives us a unique insight into the nature of SLSN."

The researchers say that the next step is to find even more distant occurrences of such events in an attempt to understand more about their variety and frequency.