A tiny black hole takes a leap through the accretion disk of a larger black hole, causing the big one to "burp". Image Source: MIT Website
Tech Bulletin – By Liu Xia
Scientists from the United States and Italy, among other countries, have formed an international research team that has detected black hole "burps" for the first time: a giant black hole burps once every 8.5 days, expelling gas from its accretion disk. The research team pointed out that a smaller black hole constantly traversing the accretion disk of the larger black hole may be the cause of its burps. The related research paper was published in the journal Scientific Reports on March 27.
The weight of this giant black hole is equivalent to 50 million times the mass of the Sun, located at the center of a galaxy 800 million light-years away from Earth. The research shows that the black hole emits a large chunk of gas every 8.5 days, and then quiets down again. The reason for the "burps" is attributed to a smaller black hole orbiting on a tilted trajectory, acting as a "partner" to the giant black hole, periodically "kicking out" gas from the accretion disk.
The lead author of the paper, Dr. Dehradun Pashaman from the Massachusetts Institute of Technology, stated that black hole "burps" indicate that accretion disks of black holes may be homes to larger celestial bodies, including other black holes and stars. An accretion disk is a super-hot gas ring rotating around a black hole. If their latest models are correct, then burping events may reveal many extreme binary star systems.
In December 2020, astronomers first noticed this giant black hole. At that time, the "SuperNova Sky Survey" telescope discovered that long-term eruptions from the black hole's accretion disk increased the brightness of a small area in the sky by 1000 times. Subsequently, data from X-ray telescopes on the International Space Station allowed scientists to catalog periodic subtle changes in the X-ray data of this giant black hole, caused by its "burps".
After analysis, the research team determined that whenever the smaller black hole passes through the accretion disk of the giant black hole, the giant black hole burps, expelling more material. They also suspect that the giant black hole will eventually devour this "partner" in over ten thousand years.
The research team stated that the weight of the smaller black hole is equivalent to 100 to 10,000 times the mass of the Sun, with a mass difference of 5,000 times between the two black holes, making it one of the most extreme mass-ratio binary systems discovered so far. In the future, they will continue to monitor this system, hoping to detect more similar systems with the recently launched "Laser Interferometer Space Antenna" (LISA) by the European Space Agency.
