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An artists concept of a white dwarf orbiting a supermassive black hole and shedding matter NASA / Aurore Simonnet, Sonoma State UniversityA supermassive black hole in a distant galaxy is once again surprising scientists.In 2018, a black hole called 1ES 1927+654, located about 270 million light-years away from Earth, showed its first signs of mysterious behavior. Its coronathe billion-degree cloud of plasma that envelopes itsuddenlydisappeared and reappeared. Now, a team of scientists at MIT have observed another novelty: X-ray radiation is emanating in pulses from the black hole with increasing frequency.Between 2022 and 2024, these flashes shifted from happening roughly every 18 minutes to occurring every 7.1 minutes. Just as its 2018 disappearing act was unprecedented at the time, the black holes current behavior marksIt was exciting in and of itself just to find these oscillations, because its only one of a handful [of supermassive black holes that do this], says lead researcher Megan Masterson, an astrophysicist at MIT, to New Scientists Alex Wilkins. But I think the most exciting thing to us was that the oscillation periodhow fast these oscillations were happeningwas changing on human-observable timescales, which is not usually what we see around supermassive black holes.The researchers presented their work on Monday at a meeting of the American Astronomical Society. The findings are set to be published in Nature in early February, and a pre-print paper, which has not yet been peer-reviewed, is currently available. Radio images show the black hole seemingly emitting pulses of plasma from both sides. NSF / AUI / NSF NRAO / Meyer at al. 2025The scientists say the most likely culprit behind the mysterious pulsing is a white dwarfa dense stellar remnant about the size of the Earththats teetering precariously close to the black hole. The white dwarf could be shedding matter and triggering the pulses observed by the researchers. As it circles closer and closer to the black hole, they hypothesize, those pulses speed up.Now, the white dwarf might be orbiting within millions of miles of the black holes event horizonthe point beyond which no matter or light can escape.This would be the closest thing that we know of around any black hole, Masterson says in a statementTo skirt so closely around the black hole without being swallowed up is a feat that other cosmic objects, such as a small black hole or a regular star, would not be able to achieve, per a statement from NASA. This helped give the team confidence that they were dealing with a white dwarf.As the black hole pulls the stellar remnant inward, the white dwarf loses matter from its outermost layer. The shedding of that material, the researchers say, provides a kick-back force in the opposite direction, preventing the white dwarf from falling into the black hole.While there could be other explanations for the mysterious X-ray patterns, such as oscillations in the black holes corona, those are less understood. But to confirm their white dwarf hypothesis, the MIT team will need to detect gravitational waves emanating from the black hole. To do so, theyll have to wait for the 2035 launch of LISA (Laser Interferometer Space Antenna), the first space-based observatory dedicated to detecting the gravitational waves produced by black holes and other powerful phenomena in the universe.But if astronomers determine a white dwarf is indeed causing the pulses, it could make the site more desirable for LISA to observe. Everyone really wants to see a white dwarf get eaten by a black hole with LISA, Matt Nicholl, an astrophysicist at Queens University Belfast in Northern Ireland who was not involved with the work, tells New Scientist. It helps tremendously if we have a few candidates.In the meantime, astronomers will keep their telescopes pointed on the black hole. The one thing Ive learned with this source is to never stop looking at it, because it will probably teach us something new, Masterson says in the statement. The next step is just to keep our eyes open.Get the latest stories in your inbox every weekday.Filed Under: Astronomers, Astronomy, Black Holes, New Research, Outer Space, telescope, universe