A black hole's winds disrupt galaxy's star formation

Ultra-fast winds from Markarian 817’s black hole are moving at a fraction of light speed.

Key Takeaways

A supermassive black hole in galaxy Markarian 817 is ejecting powerful ultra-fast winds.
These winds are cutting off the galaxy’s star-forming gas supply, effectively halting star birth.

The phenomenon was detected by ESA’s XMM-Newton telescope, revealing unexpected activity in a moderately feeding black hole.
The discovery challenges prior assumptions that only highly active black holes produce such winds.
This finding suggests such winds may be more common, potentially reshaping many galaxies.

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A New Phenomenon in Markarian 817

Astronomers have observed a supermassive black hole in the galaxy Markarian 817 (Mrk 817), located 430 million light-years away in the constellation Draco, unleashing ultra-fast winds that are disrupting its host galaxy. Detected using ESA’s XMM-Newton space telescope, this discovery marks the first instance of such winds emerging from a moderately feeding black hole, defying previous expectations.

Supermassive black holes, which can have masses millions to billions of times that of the Sun, often sit at the centers of galaxies. When surrounded by accretion disks of gas and dust, their immense gravity superheats this material, making it glow and creating active galactic nuclei (AGNs). AGNs often outshine their host galaxies and emit winds that can halt star formation.

In Mrk 817, astronomers noticed its AGN had gone unusually quiet, shrouded by X-ray-absorbing winds. These winds, lasting hundreds of days, consist of at least three components moving at fractions of the speed of light. This table-flipping activity depletes the black hole’s fuel and pushes away gas critical for star formation across the galaxy.

An illustrations shows a tantrum throwing supermassive black hole spitting out high-energy wind. (Image credit: : ESA (acknowledgement: work performed by ATG under contract to ESA))

New Insights into Black Hole Behavior

Previously, ultra-fast winds were associated only with black holes in AGNs accreting at extremely high rates. However, the Mrk 817 black hole is feeding at a moderate pace, challenging the assumption that high accretion is necessary to trigger such winds.

“This discovery changes the way we look at AGNs,” said Elias Kammoun of Sapienza University of Rome. It suggests ultra-fast winds might occur more frequently than previously thought and could play a significant role in shaping galaxies, including the Milky Way.

The findings also highlight the long-lasting impact of moderately feeding black holes. These winds can persist for extended periods, making them capable of significantly altering their host galaxies’ evolution.

A view of the galaxy Mrk 817 as seen by Hubble (Image credit: ESA)

Miranda Zak, a graduate student at the University of Michigan, led the team’s observation efforts, initially identifying the AGN’s unusual behavior with NASA’s Swift observatory before following up with XMM-Newton. This research underscores the importance of studying AGNs across different feeding rates to understand their influence on galaxy formation and evolution.

Astronomers believe this discovery is just the beginning. Future observations could reveal how common these winds are and their role in creating vast star-deprived regions in galaxies. “I believe this is just the tip of the iceberg!” Kammoun said.