Scientists have captured the “awakening” of a supermassive black hole that unexpectedly comes to life.
More than 300 light years from Earth, in the constellation of Virgo, this black hole remained quietly hidden until it reactivated without warning in 2019.
At more than 100,000 times the mass of our sun, this enormous void suddenly began to consume matter from the surrounding galaxy.
The black hole now emits so much light that an international team of scientists was able to witness the “unprecedented” moment it came back to life.
And experts say this is something that could happen in the core of our own galaxy.
Researchers have captured the moments when a terrifying black hole ‘awakens’ from its slumber and begins to consume its galaxy, as shown in this artist’s impression.
Until very recently, the galaxy SDSS1335+0728 had been just another dark and relatively uninteresting part of space.
But in December 2019, scientists noticed that the star had begun emitting massive amounts of infrared, ultraviolet, and visible light.
Paula Sánchez Sáez, an astronomer at the European Southern Observatory in Germany and lead author of the study, says: “Imagine that you have been observing a distant galaxy for years and it always seemed quiet and inactive to you.
“Suddenly, its (core) begins to show dramatic changes in brightness, unlike any typical event we’ve seen before.”
While it’s not uncommon for galaxies to get brighter, none of those explanations matched what scientists were seeing now.
Supernovae or tidal disruption phenomena, in which a star is torn apart by a black hole, produce a lot of light, but only for very short periods of time.
However, the Galaxy SDSS1335+0728 continues to get brighter more than four years after it was first “turned on.”
As this artist’s impression shows, before 2019 the galaxy was quite dim and did not feature bright light at its core. This was because the supermassive black hole at its center was dormant.
By combining observations from several telescopes around the world, including ESO’s Very Large Telescope (VLT), researchers have been able to observe this process as it unfolds.
The data they collected shows that the galaxy now produces four times as much ultraviolet radiation, twice as much infrared radiation, and has even started producing X-rays.
This provides strong evidence that the black hole has activated, making it an “active galactic nucleus.”
Co-author Lorena Hernández García, from the University of Valparaíso in Chile, says: ‘The most tangible option to explain this phenomenon is that we are seeing how the (core) of the galaxy is beginning to show activity.
“If so, it would be the first time we would see the activation of a massive black hole in real time.”
This gives scientists a unique opportunity to observe the inner workings of some of the most exotic objects in the universe.
As black holes feed, the matter that falls under their attraction becomes extremely hot and bright. Scientists believe that what they can now observe is radiation from gases falling into the black hole (artist’s impression)
Black holes are so dense that not even light can escape their gravitational pull, making them extremely difficult to observe.
Scientists can only observe the effects they have on the universe around them, either through gravitational lensing or through light emitted by superhot matter in orbit.
This means that when a black hole is inactive and no longer consuming matter, it is practically invisible to our telescopes.
Co-author Claudio Ricci, from Universidad Diego Portales in Chile, says: “These giant monsters are usually asleep and not directly visible.
“In the case of SDSS1335+0728, we were able to observe the awakening of the enormous black hole, which suddenly began to feed on the gas available in its environment, becoming very bright.”
This not only provides scientists with data about how black holes work, but could also give us a clue about the future of our Milky Way galaxy.
The largest black hole in the Milky Way is Sagittarius A*, at the center of the galaxy, which has a solar mass of about 4 million and spins so fast that it takes the shape of a soccer ball.
Although the galaxy SDSS1335+0728 is located more than 300 light-years away in a region of space called the Virgo constellation (pictured), researchers believe we could use it to learn about the supermassive black hole at the center of our own galaxy.
Pictured are instruments that make up the Very Large Telescope in the remote and sparsely populated Atacama Desert in northern Chile.
Lead author Dr Sáez told MailOnline: “The black hole at the center of our galaxy, Sagittarius A*, is currently in a quiescent phase, but we cannot rule out that it may go through a process in the future. similar to that observed in SDSS1335+0728.’
However, Dr. Sáez also notes that it is unclear how likely this is to happen.’
She says: ‘So we are not at risk and probably, if it activates, nothing will happen to the solar system, since we are very far from the center of the galaxy.
“But we will probably see some spectacular light coming from the galactic center.”
Researchers say more tests will be needed to rule out any alternative explanations, but black hole reactivation remains the most likely explanation.
For example, they note that this could be due to an exceptionally slow “tidal perturbation event,” when a star is torn apart by the strong gravitational force of a nearby supermassive black hole.
However, this would have to be the longest and weakest tidal disturbance event ever observed or some type of even more unusual and still unknown event.
Dr. Sáez concludes: “Regardless of the nature of the variations, (this galaxy) provides valuable information about how black holes grow and evolve.”