Astronomers using the James Webb Space Telescope have found three actively feeding supermassive black holes inside a single galaxy seen as it was about 1.2 billion years after the Big Bang. Two of them sit near the galaxy's center, only about 620 light-years apart, and are expected to merge within the next few hundred million years, according to the Max Planck Society.

The study, published in Astronomy & Astrophysics, drew renewed attention after a ScienceDaily summary appeared Oct. 25. The findings were first released as a preprint in September 2025 and announced by the Max Planck Society in August 2026, so this is an important result — not a breaking discovery.

It matters because it tackles a long-running puzzle. JWST keeps finding black holes that grew enormous very early in cosmic history, faster than standard models easily explain. A galaxy hosting three growing black holes at once offers a rare look at how that growth may happen.

A Galaxy Hosting Three Feeding Giants

The galaxy, J0148-4214, lies more than 12.5 billion light-years away, at a redshift of 5.02. Because its light took so long to reach us, astronomers see it as it was when the universe was less than a tenth of its current age. Its three black holes have estimated masses of about 80 million, 2 million, and 600,000 times the mass of the Sun. The two central ones are about 620 light-years apart as seen on the sky, while the third sits roughly 5,500 light-years from the center.

Lead author Hannah Übler of the Max Planck Institute for Extraterrestrial Physics called it "the first evidence of three active black holes in a single galaxy" in the distant universe. The galaxy's stars total about 1.3 billion solar masses, so the black holes make up an unusually large share of its mass.

The third black hole's origin is uncertain. It may be left over from an earlier galaxy merger, kicked outward by a recoil when two black holes combined, or slowly migrating inward.

A Small Black Hole Breaking the Speed Limit

The smallest of the three, at about 600,000 solar masses, is feeding faster than the Eddington limit. That limit is the maximum rate at which basic theory says a black hole can swallow gas, because the radiation from infalling material pushes back on fresh gas.

Exceeding it, even briefly, would let a black hole bulk up far faster than expected. The most massive black hole in the galaxy is feeding at a lower rate. Episodes of super-Eddington growth are one proposed explanation for how black holes reached millions or billions of solar masses so early.

Co-author Roberto Maiolino of the University of Cambridge said the results suggest mergers may be another fast route for that early growth. A coming merger of the central pair would combine their mass in one step, alongside steady feeding.

Spectro-Astrometry Split One Blur Into Two

At this distance, the two central black holes are too close to appear as separate points of light, even for JWST. The team used the telescope's NIRSpec integral field spectrograph, which records a spectrum at every point across the galaxy. The work is part of a JWST program called BlackTHUNDER, which studies black holes in early galaxies.

Gas whirling around each black hole moves at high speed, leaving a distinctive signature in hydrogen light. Spectro-astrometry measures tiny positional shifts in that light at different velocities, revealing that the signal comes from two slightly offset sources rather than one. The researchers said that without this spatially resolved spectroscopy, only one of the three black holes would likely have been detected.

That has a broader implication. If close black hole pairs routinely look like single objects, surveys may be undercounting multiple black holes in early galaxies. Revisiting existing JWST data with the same technique could reveal more hidden pairs and triples.

Evidence Check and What Comes Next

This is a peer-reviewed observational study of one galaxy. The central pair was inferred from spectral structure that the authors say is best explained by two black holes, not resolved directly as separate points. Black hole masses and feeding rates are estimates derived from the data. One galaxy cannot show how common such systems are, and the merger timeline is a projection based on the pair's estimated separation rather than a measured orbit. Co-authors at the Max Planck Institute for Extraterrestrial Physics, including Giovanni Mazzolari, derived the galaxy's stellar mass from the same JWST data.

The press release also describes the result as a first, a claim from the research team that has not been independently tested here.

There is no effect on Earth or daily life — the galaxy's light has traveled more than 12.5 billion years to reach us, and the merger will unfold over hundreds of millions of years. The practical payoff is scientific: better models of how black holes and galaxies grew together.

Future gravitational wave observatories, such as the planned LISA mission, are designed to detect mergers of massive black holes and could test whether such events were common in the early universe. More JWST spectroscopy should reveal whether triple systems like this one are rare or routine.

The bottom line: JWST has caught three black holes growing in one young galaxy, including a small one outpacing theory and a central pair on course to merge. The result supports the idea that both rapid feeding and mergers helped early black holes grow so large so quickly.

What Readers Want to Know

What did astronomers find? Three actively feeding supermassive black holes in one galaxy, J0148-4214, seen about 1.2 billion years after the Big Bang.

How close are the two central black holes? About 620 light-years apart as seen on the sky, and expected to merge within a few hundred million years.

What makes the smallest black hole unusual? It is feeding faster than the Eddington limit, the maximum rate basic theory predicts.

How did JWST tell them apart? Spectro-astrometry detected tiny positional shifts in hydrogen light from fast-moving gas around each black hole.

Is this a new discovery? The paper appeared as a preprint in 2025 and was announced in August 2026. It is drawing renewed attention now.

Does this affect Earth? No. The galaxy is more than 12.5 billion light-years away.