IIA astronomers confirm black hole activity curbs formation of new stars

Black Hole Activity Found to Halt Star Formation, Says IIA Study (Image: Canva)

A recent study by the Indian Institute of Astrophysics (IIA) has shed new light on how supermassive black holes can influence the life cycle of galaxies. Astronomers in Bengaluru have found that energy from these black holes can slow down or even stop the birth of new stars.

How do black holes control star formation?
Researchers at the IIA, an autonomous institute under the Department of Science and Technology (DST), revealed that radiation and jets from active galactic nuclei (AGN) can drive gas away from galaxy centres. Without this gas, stars cannot form.

“Recent advancements in instrumentation, such as integral field spectroscopy, have allowed us to study very small galactic regions,” said Prof. C. S. Stalin, a faculty member at IIA and co-author of the study. “These methods now help us explore the complex link between AGN and their host galaxies,” he told PTI.

AGN are bright centres of galaxies powered by matter falling into supermassive black holes, which are millions of times more massive than the Sun. Their intense radiation and high-speed jets are strong enough to affect the entire structure of their galaxies.

What makes this research different?
The study, led by Ph.D. student Payel Nandi, is one of the largest of its kind. Unlike previous works that focused on a few galaxies, this research studied 538 AGN. “We compared optical and radio properties and found patterns linking black hole activity, gas outflows and star formation suppression,” Nandi told PTI.

The researchers used optical data from the Sloan Digital Sky Survey (SDSS) and radio data from the Very Large Array (VLA), both located in the United States. Analysing and matching the data took nearly four months, they said. The findings have been published in The Astrophysical Journal.

What did the study reveal about galaxy evolution?
The results show that radiation from black holes is the main cause of powerful gas outflows. “These outflows are twice as common in galaxies detected in radio wavelengths — 56% compared to 25% in those without radio emission,” said Prof. Stalin.

According to Nandi, the study helps explain why some galaxies stop forming stars while others continue to thrive. “To understand galaxy evolution, we need to combine data across wavelengths — optical, radio and beyond,” she said.

She added that this approach helps scientists uncover hidden forces shaping galaxies over time. Such research is crucial for improving models and computer simulations of how galaxies evolve.

The researchers believe their findings add a vital piece to the long-standing puzzle of galaxy formation. “This comprehensive, data-driven study provides a solid base for future work on how black holes shape the universe,” said Nandi.

(Inputs From PTI)