Buried in a distant galaxy, astronomers have uncovered a black hole so massive it bends light itself.
Located some 5 billion light-years from Earth, the dormant black hole tips the scales at an astonishing 36 billion times the mass of the Sun, making it a strong contender for the most massive black hole ever detected.
It sits at the heart of the Cosmic Horseshoe, a galaxy so massive it warps spacetime, bending the light of a background galaxy into a glowing, horseshoe-shaped Einstein ring.
What makes this discovery even more extraordinary is that the black hole is completely silent — not actively consuming matter, not blasting out radiation.
Light bends, stars flee
“This discovery was made for a ‘dormant’ black hole — one that isn’t actively accreting material at the time of observation,” said lead researcher Carlos Melo of the Universidade Federal do Rio Grande do Sul in Brazil. “Its detection relied purely on its immense gravitational pull and the effect it has on its surroundings.”
To uncover the behemoth, scientists combined stellar kinematics — the study of how stars move within galaxies — with gravitational lensing, where gravity bends light.
The latter technique allowed the team to push far beyond the limits of traditional black hole detection methods, which typically only work in the nearby universe.
They observed stars near the galaxy’s center moving at nearly 400 kilometers per second, an unmistakable sign of a powerful gravitational force.
“By combining these two measurements, we can be completely confident that the black hole is real,” said Professor Thomas Collett of the University of Portsmouth.
“This is amongst the top 10 most massive black holes ever discovered, and quite possibly the most massive. Thanks to our method, we’re much more certain about its mass than most others.”
Galaxy graveyards birth giants
The galaxy housing the black hole is part of a fossil group, the cosmic endgame of galaxy evolution.
These structures form when a once-crowded galaxy group collapses into a single dominant galaxy, likely by merging with all its neighbors.
Scientists believe the black hole’s extraordinary mass may be the result of several smaller supermassive black holes merging over time, as their host galaxies collided and combined.
The discovery has far-reaching implications. Astronomers believe the growth of supermassive black holes is closely tied to the evolution of galaxies themselves. As galaxies grow, they funnel matter into their central black holes.
Some of this matter fuels the black hole, but much of it is blasted back out in energetic jets as quasars: blazing beacons that can heat and blow away gas, preventing new stars from forming.
“We think the size of both is intimately linked,” said Collett. “Quasars dump huge amounts of energy into their host galaxies, which stops gas clouds condensing into new stars.”
Our own Milky Way hosts a relatively modest 4 million solar mass black hole at its center. It’s quiet today, but astronomers expect it to roar to life again. When the Milky Way and Andromeda galaxies merge in about 4.5 billion years, that galactic collision could reignite our central black hole into a quasar.
Ironically, this groundbreaking discovery wasn’t even the team’s original goal. They were studying the dark matter distribution in the Cosmic Horseshoe when the signature of the black hole emerged unexpectedly.
Now, with their method validated, the researchers plan to apply it using data from the European Space Agency’s Euclid space telescope, opening the door to uncovering many more of the universe’s hidden, silent giants.
The study is published in the journal Monthly Notices of the Royal Astronomical Society.
FAQs
- What is a black hole?
Black holes are regions in spacetime where a lot of matter is crammed into a very tiny space. They are formed after a star dies. - Who discovered black holes?
The idea of black holes was first proposed by John Michell in 1783. The concept was, however, further developed through Einstein’s theory of general relativity. - What is the biggest black hole known to mankind?
Ton 618 was the biggest black hole known to man until this discovery. Residing at the center of the Quasar, contains a whopping 66 billion times the mass of our sun