Skip to main content
  1. Home
  2. Space
  3. News

Astronomers just spotted the largest cosmic explosion ever seen

Georgina Torbet
By

Astronomers recently observed the largest cosmic explosion ever seen, far brighter than a supernova and lasting for much longer too. They believe that the outpouring of light is due to a supermassive black hole devouring a large cloud of gas.

Some of the brightest events seen in the sky are supernovae, which are huge explosions that occur when a massive star comes to the end of its life. But the recently observed event, called AT2021lwx, was 10 times brighter than any known supernova. Supernovae also typically last for a few months, but this event has been shining out for several years.

Artist’s impression of a black hole accretion.
Artist’s impression of a black hole accretion. John A. Paice

“We came upon this by chance, as it was flagged by our search algorithm when we were searching for a type of supernova,” said lead researcher Philip Wiseman of the University of Southampton in a statement. “Most supernovae and tidal disruption events only last for a couple of months before fading away. For something to be bright for two plus years was immediately very unusual.”

Related Videos

The researchers used several ground-based telescopes to observe the event, which had first been spotted in 2020. Because of how far away the explosion is, the event must have occurred around 8 billion years ago.

While bright events involving the supermassive black holes at the heart of galaxies typically show brightness rising and falling, that wasn’t the case here. “Looking back over a decade there was no detection of AT2021lwx, then it suddenly appeared as one of the most luminous things in the universe, which is unprecedented,” said co-author Mark Sullivan.

The researchers can’t say for certain what caused the explosion, but one theory is that it occurred when an enormous cloud of hydrogen gas strayed too close to a supermassive black hole, and parts of it were devoured as they passed the event horizon. That caused shock waves throughout the rest of the cloud and other material circling the black hole.

To understand more about the event, the researchers plan to observe it in different wavelengths such as X-rays. Upcoming telescopes like the Vera Rubin Observatory will also be able to look for other similar events, as it will perform regular surveys of half of the night sky to identify changes and spot transient events.

“With new facilities, like the Vera Rubin Observatory’s Legacy Survey of Space and Time, coming online in the next few years, we are hoping to discover more events like this and learn more about them,” Wiseman said. “It could be that these events, although extremely rare, are so energetic that they are key parts of how the centers of galaxies change over time.”

The research is published in the journal Monthly Notices of the Royal Astronomical Society.

Editors' Recommendations

Topics
Georgina Torbet
Georgina Torbet
Space Writer
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
How astronomers worked together to spot an asteroid before it hit Earth
This time-lapse photograph was taken by astronomer Robert Weryk from near his home in London, Ontario, Canada, after NASA’s Scout system forewarned him about the entry of 2022 WJ1 on Nov. 19, 2022. The resulting fireball streaked directly overhead and continued east until it broke up.

This month, a small asteroid hurtled through space toward the Earth and entered the sky above Toronto. Even though it was only around a meter across and burnt up harmlessly in the atmosphere, this asteroid was notable because it was one of the first few asteroids to strike Earth that we knew was coming.

The asteroid, named 2022 WJ1, was first discovered by a project called the Catalina Sky Survey which uses a telescope at the Catalina Station near Tucson, Arizona. It was seen around four hours before it was due to strike Earth, making it just the sixth asteroid to date identified before impacting Earth. The detection was passed to a group called the Minor Planet Center which brings together international data on near-Earth objects and coordinates follow-up observations with astronomers around the world.

Read more
Listen to the spooky echoes of a black hole
The black hole in V404 Cygni is actively pulling material away from a companion star — with about half the mass of the Sun — into a disk around the invisible object. A burst of X-rays from the black hole detected in 2015 created the high-energy rings from a phenomenon known as light echoes, where light bounces off of dust clouds in between the system and Earth. In these images, X-rays from Chandra are shown, along with optical data from the Pan-STARRS telescope that depict the stars in the field of view.

As well as admiring beautiful pictures of space, you can also listen to those pictures via sonifications. These take images and translate them into eerie sounds to illustrate the wonderful and strange phenomena of our universe. NASA's latest sonification illustrates the rings of X-rays that have been observed echoing around a black hole in the V404 Cygni system.

Quick Look: 'Listen' to the Light Echoes From a Black Hole

Read more
James Webb spots two of the earliest galaxies ever seen
Two of the most distant galaxies seen to date are captured in these Webb pictures of the outer regions of the giant galaxy cluster Abell 2744. The galaxies are not inside the cluster, but many billions of light-years behind it. 

The James Webb Space Telescope has discovered two of the earliest galaxies ever seen in the universe, and they are much brighter than expected, meaning astronomers are rethinking their beliefs about how the earliest stars formed.

"These observations just make your head explode," said Paola Santini, one of the researchers, in a statement. "This is a whole new chapter in astronomy. It’s like an archaeological dig, when suddenly you find a lost city or something you didn’t know about. It’s just staggering."

Read more