Supermassive black holes could be the universe's biggest planet nurseries

May 31, 2026 report Supermassive black holes could be the universe's biggest planet nurseries Paul Arnold Author Lisa Lock Scientific Editor Robert Egan Associate Editor Supermassive black holes are the largest known black holes in the universe, sitting at the center of most large galaxies. They are sometimes described as cosmic monsters because they feed on surrounding gas and dust when they are active, as well as destroy anything that gets too close. But their reputation could be due for a rethink, as a new paper published on the arXiv preprint server suggests they may also be the birthplace of millions of planets. Hidden planet nurseries Planet formation is a complex process that scientists believe occurs in disks of gas and dust spinning around young stars. Giant versions of these disks also exist around supermassive black holes at the center of active galaxies (known as active galactic nuclei or AGNs). More specifically, the outer edges of these black hole disks, called tori, have temperatures and conditions similar to those found in planet-forming disks around stars. This may allow dust to survive long enough to clump together and eventually form planets. To see whether this could be the case, Barry McKernan of the City University of New York and colleagues set out to find some answers. The team fed data on temperatures and gases in the outer ring into a computer model of a magnetized black hole disk and calculated key aspects of planet formation. These included how fast dust clumps together and the final size of the planets. They also looked at how much extra dust and gas these newborn worlds could swallow up over millions of years, to estimate how massive they might eventually become. New worlds in new places According to the modeling and calculations, planets can form in these extreme environments around supermassive black holes. Not only that, but in vast numbers, as the researchers write in their paper. "Our approximate model suggests that AGN dust tori host the largest populations of planets in the universe." The findings also show that they can grow much faster than planets born around normal stars. The intense gravity and dense materials in the AGN environment may allow young planets to rapidly gain mass, potentially growing far larger than Earth and even exceeding the size of Jupiter. Some of these new worlds could eventually accrete so much gas and dust that they could become new stars. As the authors note, "Vigorous accretion can occur, leading to objects with stellar masses—defining a core accretion channel for star formation." The paper also predicts the possible formation of exotic massive objects made mostly from dust, unlike anything known in planetary systems around ordinary stars. The research provides astronomers with plenty of food for thought, though the ideas will need observational evidence to support them. Written for you by our author Paul Arnold, edited by Lisa Lock, and fact-checked and reviewed by Robert Egan—this article is the result of careful human work. We rely on readers like you to keep independent science journalism alive. If this reporting matters to you, please consider a donation (especially monthly). You'll get an ad-free account as a thank-you. Publication details Bhupendra Mishra et al, Active Galactic Nucleus Tori: Potential Birthplace to Millions of Planets, arXiv (2026). DOI: 10.48550/arxiv.2605.19241 Journal information: arXiv Key concepts Astronomical black holesPlanets & planetary systemsStarsExoplanet systemsCircumstellar disksAccretion© 2026 Science X Network