Supermassive black holes influence galaxy evolution by launching jets that disrupt gas in the circumgalactic medium, suppressing star formation, according to a study led by Arizona State University and Raman Research Institute researchers.
Scientists have uncovered how jets from supermassive black holes can “kill” their host galaxies by disrupting star-forming gas far beyond their visible boundaries. The research, published in the Astrophysical Journal Letters, reveals that these plasma jets, extending hundreds of thousands of light-years, heat and ionize gas in the circumgalactic medium (CGM), preventing it from cooling and collapsing into new stars. The study was announced by Arizona State University on September 24, 2026, and published with DOI 10.3847/2041-8213/ae9cbd.
How Jets Disrupt Star Formation
The study, led by Arizona State University’s Sanchayeeta Borthakur and Raman Research Institute’s Namrata Roy, analyzed data from the Dark Energy Spectroscopic Instrument (DESI) and the LOFAR Two-meter Sky Survey (LoTSS). By stacking observations of hundreds of galaxies with active jets, researchers detected bright H-alpha emissions—ionized hydrogen—along jet paths, particularly near the CGM’s outer edge. This indicates jets transfer energy to gas, heating it and halting star formation. The findings were reported by Phys.org, crediting Arizona State University for the original coverage.
A black hole is incredibly small compared to a galaxy, but its impact can reach hundreds of thousands of light-years,
Roy said. The jet carries the energy outward, and the gas lights up along its path.
The team found the strongest effects where jets first collide with the CGM and at its outermost fringes, where energy release is most intense. According to the study, this energy transfer occurs at distances of hundreds of thousands of light-years, as noted in Space coverage.
The research also linked the findings to Sagittarius A*. The study’s authors emphasized that jets can “brake” star formation by preventing gas from cooling and falling into galaxies, a process described as a “quenching” of star birth. This aligns with observations from universemagazine.com, which highlighted the role of the CGM in regulating star formation.
Key Observational Evidence
Researchers observed that hydrogen emissions aligned with jet directions, while cooler gas remained uniform. This suggests jets selectively ionize gas along their path, rather than uniformly affecting the CGM. The study also noted that jets could “brake” star formation by preventing gas from cooling and falling into galaxies. The surprising question is: How can something so small energetically impact something so enormous?
Roy asked. The findings offer a new way to test how black hole feedback shapes galaxy evolution, with implications for understanding why some galaxies become quiescent while others continue forming stars.
The team’s analysis revealed that H-alpha signals along jets were about 100 times brighter than the normal halo, indicating strong ionization. This contrast between directional and uniform gas tracers was critical for understanding jet impacts. The study’s methodology, combining DESI optical data with LOFAR radio measurements, allowed researchers to trace energy distribution across the CGM, as detailed in Space and Universetoday reports.
Broader Implications for Galaxy Evolution
The research highlights the critical role of black hole jets in regulating galaxy growth. By heating and disturbing the CGM, jets can suppress star formation over vast distances, altering a galaxy’s long-term fate. This mechanism helps explain why galaxies with ample gas reserves often stop forming stars despite having the raw materials. By heating, stirring, and disturbing gas throughout the CGM, jets can prevent that gas from cooling down and falling inward to fuel new stars. The findings provide observational evidence for theories of how black holes influence galaxy evolution.
Understanding these processes may also shed light on the Milky Way’s own history, as its central black hole, Sagittarius A*, may have once influenced the CGM through a burst of activity several million years ago. The research was cited in Eurasia Review.
Methodology and Future Research
The team combined optical data from DESI with radio measurements from LoTSS, focusing on jets’ directional impact. By analyzing H-alpha emissions along jet axes, they detected signals about 100 times brighter than the normal halo. This approach revealed how jets interact with gas in ways previously obscured by averaging observations across all directions. The study’s methodology was detailed in universemagazine.com, which noted the significance of detecting ionized hydrogen glow along jet paths.
The research also connected jets to the CGM’s role in galaxy evolution. By demonstrating how jets energize gas at the CGM’s outer edge, the study provides a framework for testing models of galaxy quenching. The findings were reported by Space, which emphasized the scale of the connection between black holes and galactic evolution.