Black holes are the notorious loners of the universe since getting close to them usually means catastrophic destruction. The latest victim who attempted friendship with one of these hungry giants ended up causing the most energetic explosion to ever occur in the universe.
In a new study, published in Science Advances, a team of astronomers from the University of Hawai’i describes what they are calling “extreme nuclear transients” (ENTs). ENTs occur when stars more than three times the weight of the Sun get too close to a supermassive black hole. In response, the black hole slowly drains the life out of the star, creating a bright, energy surge unlike anything we’ve ever observed before.
“We’ve observed stars getting ripped apart as tidal disruption events for over a decade, but these ENTs are different beasts, reaching brightnesses nearly ten times more than what we typically see,” said Jason Hinkle, who led the study, in a press release. “Not only are ENTs far brighter than normal tidal disruption events, but they remain luminous for years, far surpassing the energy output of even the brightest known supernova explosions.”
What Makes Extreme Nuclear Transients Different?
The amount of energy and brightness emitted by ENTs is unusual and unequaled in the history of the cosmos. The closest energy bursts to rival ENTs are supernovae, which are when stars explode in colossal fashion. Supernovae are extraordinary phenomena, with each explosion emitting the same amount of energy in one year as our Sun does in its entire lifetime.
But even the most energetic supernova ever observed pales in comparison to an ENT, which emits 25 times more energy. A single ENT dwarfs the power of a supernova, radiating the energy of 100 Suns in the same time period a supernova radiates the energy of one Sun.
Read More: Supernova Helps Explain the Creation of Cosmic Dust Storms in Elliptical Galaxies
The Star and the Black Hole
The team at the University of Hawai’i knew the phenomena they were observing weren’t supernovae and were curious as to what they were looking at and how these events radiated so much bright energy. Getting the answer took a global effort, and lots of time and patience, as ENTs take several years to fully evolve.
What they discovered was that the secret to these bright, energy emissions from the ENTs lay in black hole anatomy. As we know, black holes are able to grow thanks to their voracious consumption of matter — a process called accretion.
After looking at the massive energy budget of ENTs and their distinct appearance, astronomers were able to land on accretion to explain what was happening between the star and the supermassive black hole. Pictures of ENTs show smooth, long-lasting curves of light that indicate the black hole is slowly ripping the star apart in order to grow bigger itself.
“These ENTs don’t just mark the dramatic end of a massive star’s life. They illuminate the processes responsible for growing the largest black holes in the universe,” said Hinkle in the press release.
A Glimpse Into The Past
The discovery and observation of ENTs is allowing astronomers to time-travel to a distant past without having to leave the comfort of their telescope. Although ENTs are rare, occurring 10 million times less frequently than supernovae, continuous monitoring of the cosmos can provide new insights into these events that will revolutionize our understanding of black hole activity.
“ENTs provide a valuable new tool for studying supermassive black holes in distant galaxies. Because they’re so bright, we can see them across vast cosmic distances – and in astronomy, looking far away means looking back in time,” said Benjamin Shappee, Associate Professor at the University of Hawai’i and study co-author, in the press release.
“By observing these prolonged flares, we gain insights into black hole growth when the universe was half its current age, when galaxies were happening places – forming stars and feeding their supermassive black holes 10 times more vigorously than they do today,” Shappee concluded in a press release
Read More: Here’s What Would Happen If You Walked Through a Black Hole
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
Science Advances. The most energetic transients: Tidal disruptions of high-mass stars
NASA. Anatomy of a Black Hole
As the marketing coordinator at Discover Magazine, Stephanie Edwards interacts with readers across Discover's social media channels and writes digital content. Offline, she is a contract lecturer in English & Cultural Studies at Lakehead University, teaching courses on everything from professional communication to Taylor Swift, and received her graduate degrees in the same department from McMaster University. You can find more of her science writing in Lab Manager and her short fiction in anthologies and literary magazine across the horror genre.
