Supermassive “bubbles” in space might have been created by a single event originating at the black hole near the center of our galaxy, a Taiwanese researcher said on Thursday.
The successful simulation of a theoretical model lent credence to the hypothesis that Fermi “bubbles,” as well as the microwave haze, were the result of a single jet event from the central black hole, said Karen Yang (揚湘怡), an associate professor in National Tsing Hua University’s Institute of Astronomy.
The theoretical model would extend understanding of activity at the center of the Milky Way and the correlation of supermassive black hole and galaxy co-evolution in the context of galaxy formation, said the abstract of a paper titled “Fermi and eROSITA bubbles as relics of the past activity of the Galaxy’s central black hole,” which was published in the journal Nature Astronomy this month.
Photo courtesy of National Tsing Hua University
University of Michigan Department of Astronomy associate professor Mateusz Ruszkowski and University of Wisconsin-Madison professor Ellen Zweibel were the coauthors.
The origin of the bubbles and the microwave haze has been intensely debated since their discovery, Yang said.
As the bubbles and the haze have “symmetry about the galactic center,” the team hypothesized that they originated from energetic outbursts, she said.
The central black hole has absorbed 10,000 to 100,000 times the mass of our sun, but only some of that mass has passed the event horizon — the “point of no return” — with most of it spat out at nearly the speed of light, Yang said.
Using a numerical simulation, the team demonstrated how the model can reproduce a process to create the bubbles and haze, the study said.
“It allows us to derive critical constraints on the energetics and timescales of the outburst,” the paper said.
The study demonstrates how supermassive black holes evolve and the co-evolution of such features in other galaxies, Ruszkowski said, adding that perhaps researchers might one day answer how such “bubbles” affect galactic evolution.
The eROSITA X-ray instrument, which was built by the Max Planck Institute for Extraterrestrial Physics in Germany, is part of the Russian-German Spektr-RG space observatory.
The Fermi bubbles were previously discovered by the Fermi Gamma-ray Space Telescope.
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