In 2019, astronomers first detected the event when a star ventured too close to a black hole, resulting in the star's destruction by the black hole's gravitational forces. The star's remains formed a disk that now encircles the black hole. Over time, this debris disk expanded and is now crashing into another star or a stellar-mass black hole orbiting at a previously safe distance. This newly battered object collides with the disk every 48 hours, producing X-ray bursts, which were captured by Chandra.

"Imagine a diver repeatedly going into a pool and creating a splash every time she enters the water," explained Matt Nicholl of Queen's University Belfast, the lead author of the study published in *Nature*. "The star in this comparison is like the diver and the disk is the pool, and each time the star strikes the surface, it creates a huge 'splash' of gas and X-rays."

Such violent star disruptions, known as tidal disruption events, are often observed when objects stray too close to black holes. However, this recent discovery shows a connection between these events and a different cosmic phenomenon known as quasi-periodic eruptions-regular bursts of X-rays linked to supermassive black holes.

"There had been feverish speculation that these phenomena were connected, and now we've discovered the proof that they are," said co-author Dheeraj Pasham of the Massachusetts Institute of Technology. "It's like getting a cosmic two-for-one in terms of solving mysteries."

The tidal disruption event, designated AT2019qiz, was first detected by the Zwicky Transient Facility in 2019. Over time, NASA's Chandra, Hubble Space Telescope, NICER, and other observatories gathered data, revealing that the debris from the destroyed star had expanded enough to repeatedly collide with another orbiting object.

"This is a big breakthrough in our understanding of the origin of these regular eruptions," commented Andrew Mummery of Oxford University. "We now realize we need to wait a few years for the eruptions to 'turn on' after a star has been torn apart because it takes some time for the disk to spread out far enough to encounter another star."

These findings could help astronomers locate more quasi-periodic eruptions, providing opportunities to measure objects in close orbits around supermassive black holes. Such discoveries might also contribute to future gravitational wave observatories.

Research Report:Quasi-periodic X-ray eruptions years after a nearby tidal disruption event

Related Links
Chandra X-ray Observatory
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