Black holes kind of do the same thing while feeding, they said. Babies frequently burp while drinking milk, while adults can hold in the burp for a more extended amount of time. The team compared black hole feeding to our eating or drinking activity by equating this transition to a human belch. This transition of variability pattern happens at a characteristic timescale that is longer for more massive black holes. For accreting SMBHs, the variability pattern changes from short timescales to long timescales. Astronomers can quantify this flickering pattern by measuring the power of the variability as a function of timescales. The light flickers are random fluctuations in a black hole’s feeding process, the researchers said. The researchers then compared the results with accreting white dwarfs, the remnants of stars like our sun, and found that the same timescale-mass relation holds, even though white dwarfs are millions to billions times less massive than SMBHs. They identified a characteristic timescale, over which the pattern changes, that tightly correlates with the mass of the SMBH. The team compiled a large data set of actively feeding SMBHs to study the variability pattern of flickering. “There have been many studies that explored possible relations of the observed flickering and the mass of the SMBH, but the results have been inconclusive and sometimes controversial,” Burke said. Due to physical processes that are not yet understood, it displays a ubiquitous flickering over timescales ranging from hours to decades. The observed light from an accreting SMBH is not constant. The findings are published in the journal Science. The new study, led by the University of Illinois Urbana-Champaign astronomy graduate student Colin Burke and professor Yue Shen, uncovered a definitive relationship between the mass of actively feeding SMBHs and the characteristic timescale in the light-flickering pattern. A black hole time machine could allow an astronaut to find out what the world will be like in the future.Align image left align image center align image right An astronaut could take a short trip near a black hole and return to Earth after years, decades, or even centuries had passed there. Someday humans might be able to use black holes to time travel forward. When the spacewalker returned to the spaceship after an hour-long spacewalk, years would have passed for those aboard the spacecraft. But if anyone back on the spacecraft could observe the astronaut’s watch from far away, they’d see its hands slow down as the spacewalker got closer to the black hole. If an astronaut left his spacecraft to explore a black hole up close, he’d see the hands on his watch ticking at normal speed. The intense gravity near a black hole makes time behave in strange ways. (A* is scientist-code for “A-star.”) The most common type of black holes, stellar black holes, are only up to 20 times more massive than our sun. This is the kind of black hole that’s at the center of our galaxy, the Milky Way it’s called Sagittarius A*. They’re up to one million times more massive than our sun. Supermassive black holes are the largest type of black hole. Though astronomers can’t see black holes, they know they’re there by the effect they have on objects that get too close. That’s why we can’t see black holes in space-they've gobbled up all the light. This includes light, the fastest thing in the universe. Nothing can move fast enough to escape a black hole’s gravity. The giant star is eventually squashed into a supersmall dot you can’t see.Ī black hole’s gravity, or attractive force, is so strong that it pulls in anything that gets too close. This causes an explosion called a supernova. The star implodes, and its center collapses under its own weight. Most black holes, regardless of their size, are born when a giant star runs out of energy. At the center of most galaxies is one of the strangest and deadliest things in the universe: a black hole.
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