Astronomers have uncovered new evidence that helps solve one of space’s biggest mysteries—the existence of intermediate-mass black holes, or IMBHs.
These black holes are heavier than the ones formed by dying stars but lighter than the supermassive giants found in the centers of galaxies.
Despite their expected presence, they’ve been incredibly hard to find, earning the nickname “missing links” in black hole evolution.
Now, a team of researchers led by Assistant Professor Karan Jani from Vanderbilt University has made a breakthrough.
Four new scientific studies from his lab shine light on the nature of these elusive objects.
The most important paper, published in Astrophysical Journal Letters, was led by postdoctoral fellow Anjali Yelikar and Ph.D. student Krystal Ruiz-Rocha.
The team went back to data from the LIGO and Virgo gravitational-wave detectors—observatories that listen for ripples in space-time caused by massive cosmic events like black hole collisions.
Their analysis found signals from black hole mergers involving objects between 100 and 300 times the mass of our sun.
These are the heaviest black holes ever seen in gravitational wave data, and they fall directly into the intermediate-mass category. According to Jani, black holes are like “cosmic fossils” that hold secrets about the earliest stars in the universe.
However, studying IMBHs is challenging because Earth-based detectors like LIGO only catch the final moments of their violent collisions. To learn more, the team looked ahead to the upcoming LISA (Laser Interferometer Space Antenna) mission—an ambitious project by NASA and the European Space Agency scheduled for launch in the late 2030s. Unlike Earth-bound detectors, LISA will float in space and can detect gravitational waves years before black holes collide, offering more detailed information about how these objects form and where they come from.
Two more studies from the team, published in The Astrophysical Journal, explored how LISA will help track these mysterious black holes over time and even measure the “kicks” they receive after merging—similar to a cosmic recoil.
The fourth study tackled another problem: how to make sure the signals scientists detect aren’t distorted by background noise. Led by postdoctoral researcher Chayan Chatterjee, this study used artificial intelligence to filter out interference, making gravitational-wave observations more reliable. This work is part of Jani’s AI for New Messengers Program, done in partnership with Vanderbilt’s Data Science Institute.
The research team is also exploring even more futuristic ideas—like using detectors placed on the moon to observe lower-frequency gravitational waves that Earth-based instruments can’t pick up. This could help scientists learn more about the environments where intermediate-mass black holes live.
Professor Jani has also been invited to help identify ideal lunar sites for future NASA missions. He’s working with the National Academies to explore how human exploration of the moon could support astronomy, space weather research, and fundamental physics.
“This is a rare and exciting moment,” Jani said. “We’re not only discovering new black holes—we’re building the future of space science from the ground up, and even from the moon.”
