Science News

from research organizations

Monster black holes are silencing star formation across the universe

Giant black holes may be secretly controlling how entire clusters of galaxies grow.

Date:

March 30, 2026

Source:

University of Arizona

Summary:

A blazing supermassive black hole can influence far more than its own galaxy. Scientists found that quasars emit radiation strong enough to shut down star formation in nearby galaxies millions of light-years away. This could explain why some galaxies near early quasars appear faint or missing. The finding suggests galaxies grow and evolve together, not in isolation.

Facebook

Twitter

FULL STORY

Artist's concept of a galaxy with a brilliant quasar – an active supermassive black hole millions to billions of times the mass of the sun – at its center. Among the brightest objects in the universe, quasars feed on infalling matter and unleash torrents of winds and radiation, shaping the galaxies in which they reside. Credit: NASA, ESA, Joseph Olmsted (STScI)

Powerful radiation from active supermassive black holes, which are believed to sit at the center of most galaxies, can do more than shape their own surroundings. A new study led by Yongda Zhu at the University of Arizona suggests these black holes can also slow the formation of stars in galaxies located millions of light-years away.

"Traditionally, people have thought that because galaxies are so far apart, they evolve largely on their own," said Zhu, the study's lead author, whose findings were published in The Astrophysical Journal Letters. "But we found that a very active, supermassive black hole in one galaxy can affect other galaxies across millions of light-years, suggesting that galaxy evolution may be more of a group effort."

Zhu describes this concept as a "galaxy ecosystem," comparing it to interconnected ecosystems on Earth. "An active supermassive black hole is like a hungry predator dominating the ecosystem," he said. "Simply put, it swallows up matter and influences how stars in nearby galaxies grow."

What Makes Supermassive Black Holes So Powerful

Black holes have fascinated scientists and the public since they were first proposed in the early 1900s. These objects represent some of the most extreme conditions in the universe, with gravity so strong that nearby matter and even light can be pulled in if they get too close.

A special category known as supermassive black holes, including the one at the center of the Milky Way, can contain millions or even billions of times the mass of the sun. Although black holes themselves cannot be seen, they can become incredibly bright when actively consuming surrounding material.

During this active phase, known as a quasar, gas and dust form a spinning disk around the black hole, releasing enormous amounts of energy as it falls inward. These quasars can shine so intensely that they outshine their entire host galaxy.

JWST Mystery Leads to a New Discovery

Early data from the James Webb Space Telescope revealed something unexpected. Astronomers noticed that regions around some of the brightest quasars in the early universe appeared to contain fewer galaxies than anticipated. Since large galaxies typically form in dense clusters, this raised questions.

"We were puzzled," said Zhu. "Was the expensive JWST broken?" he added with a laugh. "Then we realized the galaxies might actually be there, but difficult to detect because their very recent star formation was suppressed."

This insight led researchers to consider a new possibility. Perhaps the intense radiation from quasars was not only affecting their own galaxies, but also limiting star formation in nearby ones.

Evidence That Quasars Suppress Star Formation

To explore this idea, the research team focused on one of the brightest known quasars, J0100+2802. This object is powered by a supermassive black hole with a mass about 12 billion times that of the sun. Because its light has traveled for more than 13 billion years, it provides a glimpse into the universe when it was less than a billion years old.

Using JWST, the team measured emissions from O III, an ionized form of oxygen that signals recent star formation. They found that galaxies within about a million light-years of the quasar showed weaker O III emissions compared to their ultraviolet light. This pattern indicates that star formation had recently been suppressed in those galaxies.

"Black holes are known to 'eat' a lot of stuff, but during the active eating process and in their luminous quasar form, they also emit very strong radiation," said Zhu. "The intense heat and radiation split the molecular hydrogen that makes up vast, interstellar gas clouds, quenching its potential to accumulate and turn into new stars."

How Radiation Disrupts Star Birth

Stars form under very specific conditions, relying on large amounts of cold molecular hydrogen gas. This gas acts as the raw material for building ne