Cosmic Leviathan Spotted: Most Massive Black Hole Ever Found
Defies Limits, Distorts Light in Galactic Horseshoe
Astronomers have identified a colossal black hole, potentially the most massive ever observed, pushing the boundaries of cosmic possibility. This titan is an astonishing 10,000 times heavier than the black hole at our Milky Way’s core.
A Gravitational Spectacle
The behemoth resides within the “Cosmic Horseshoe,” a galaxy so immense it warps the fabric of spacetime. This distortion bends light from a background galaxy into a stunning horseshoe-shaped Einstein ring, a direct testament to its extreme gravitational influence.
Recent findings, published August 7 in the *Monthly Notices of the Royal Astronomical Society*, reveal the ultramassive black hole’s mass to be an astounding 36 billion times that of our Sun. It’s believed that every galaxy hosts a central supermassive black hole, with larger galaxies harboring these “ultramassive” giants.
“This is amongst the top 10 most massive black holes ever discovered, and quite possibly the most massive.”
—Professor Thomas Collett, Researcher at the University of Portsmouth
Professor Collett elaborated on the measurement’s certainty: “Most of the other black hole mass measurements are indirect and have quite large uncertainties, so we really don’t know for sure which is biggest. However, we’ve got much more certainty about the mass of this black hole thanks to our new method.”
Pioneering Detection Method
The detection utilized a novel combination of gravitational lensing and stellar kinematics. While stellar kinematics is considered the gold standard for measuring black hole masses, it’s typically limited to nearby galaxies where the central regions are resolvable.
The team overcame this challenge by integrating gravitational lensing, which allowed them to “push much further out into the universe,” according to Professor Collett. The black hole’s presence was confirmed by two effects: altering light paths and accelerating stars within its host galaxy to nearly 400 km/s.
“We detected the effect of the black hole in two ways – it is altering the path that light takes as it travels past the black hole and it is causing the stars in the inner regions of its host galaxy to move extremely quickly (almost 400 km/s). By combining these two measurements we can be completely confident that the black hole is real.”
—Professor Thomas Collett, Researcher at the University of Portsmouth
Carlos Melo, a PhD candidate at the Universidade Federal do Rio Grande do Sul (UFRGS) in Brazil, highlighted the significance of detecting a “dormant” black hole: “Its detection relied purely on its immense gravitational pull and the effect it has on its surroundings.”
“What is particularly exciting is that this method allows us to detect and measure the mass of these hidden ultramassive black holes across the universe, even when they are completely silent.”
—Carlos Melo, PhD Candidate at the Universidade Federal do Rio Grande do Sul (UFRGS)
Located approximately 5 billion light-years away, the Cosmic Horseshoe black hole’s mass was determined using a method that provides more direct and robust measurements compared to indirect, accretion-based estimates, which often carry significant uncertainties.
This discovery is crucial for understanding the intricate link between supermassive black holes and their host galaxies. Researchers posit a strong correlation, where galaxies funnel matter to their central black holes, influencing growth and star formation through quasar activity.
Galactic Evolution’s Endpoint
The Cosmic Horseshoe’s host galaxy is identified as a “fossil group,” representing the final stage of massive, gravitationally bound structures. These form when smaller galaxies merge into a single, extremely massive galaxy, devoid of bright companions.
Professor Collett suggests this scenario implies that black holes from merged galaxies have coalesced into the detected ultramassive black hole, offering a glimpse into the “end state of galaxy formation and the end state of black hole formation.”
This significant finding emerged from research initially focused on the galaxy’s dark matter distribution. The research team plans to leverage data from the European Space Agency’s Euclid space telescope to identify more supermassive black holes and their hosts, aiming to unravel how these objects regulate galaxy star formation. For context, as of 2024, astronomers have identified over 100 supermassive black holes in the observable universe, according to NASA.
