This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility: An early-career Western Australian astrophysicist has helped uncover a universal rule behind one of the most powerful behaviors in the universe: when black holes launch jets. The discovery, published in the journal Nature Astronomy, shows black holes appear to fire off powerful jets at the same critical point in their feeding cycle—whether they are about 10 times the mass of the sun or millions of times heavier.
Adelle Goodwin, an astrophysicist at Curtin University's International Center of Radio Astronomy Research (ICRAR) and a Forrest Research Foundation fellow, with co-author Dr. Andrew Mummery from the Institute for Advanced Study in Princeton. The finding is the result of years spent piecing together observations from telescopes around the world, including Australia, the United States, India, South Africa and space—tracking rare events where stars are torn apart by supermassive black holes and watching what happens next and why.
The moment the pattern clicked came not at a telescope console but in a bar in Madrid while attending a conference, where Goodwin and Mummery realized the same jet-launching rule seen in small black holes also appeared to hold true for supermassive ones. Goodwin said the breakthrough came from trying to answer the following question: Why do some black holes produce radio jets soon after tearing apart a star, while others appear to switch on months or years later? "We were looking at these events and asking why the timing was so different," Goodwin said.
"Then the pattern became clear. The delayed jets were appearing when the black hole's feeding rate dropped to the same critical point already known from much smaller black holes. "That was the moment we realized this was not just a quirk of one type of black hole, but it looked like a rule that applied across the universe." Black holes are often described as cosmic vacuum cleaners, but Goodwin said they were more like messy eaters.
"When a black hole tears apart a star, it does not swallow everything neatly," Goodwin said. "Some of the material is consumed, and some is launched back into space in powerful jets and outflows. "You can think of it as a black hole burp, except these burps can blast material across enormous distances and influence the galaxies around them." For decades, astronomers have suspected black holes might follow the same basic physics regardless of their size—but proving it has been difficult because supermassive black holes usually evolve over thousands of years.
Goodwin found a way around that problem by studying tidal disruption events, which occur when a star strays too close to a supermassive black hole and is ripped apart. These rare events compress a supermassive black hole feeding episode into years rather than millennia, giving astronomers a chance to watch the process unfold. The researchers analyzed 20 tidal disruption events using optical, ultraviolet, X-ray and radio observations, narrowing the sample to 10 events where they could reliably model both the black hole's feeding rate and the timing of its radio outflows.
Extract — continue reading at the source.
