This Black Hole’s Behavior Proves We Still Don't Know Enough About Them

Photo Credit: DESY, Science Communication Lab

Black holes are among the biggest mysteries of the universe. They are known to have an enormous gravitational pull and they absorb everything that comes in their proximity. But that might not be completely true. Nothing certainly escapes passing through the event horizon but there is an area around the black hole where the gravitational pull is strong but things can still exist.

Not just that, black holes also spew some amount of matter, which gets thrown out at great speeds when material falls into the black hole. Scientists still haven’t managed to completely understand how a black hole works. A new study might have revealed another detail about this mysterious space object. The research has been published in The Astrophysical Journal.

Something Strange With This Black Hole

Astronomers have recently discovered something strange where a black hole is throwing out material years after it swallowed a star. The black hole AT2019dsg is around 665 million light-years away from our planet, and scientists observed it ripping apart the star in 2018. However, it became active again last year.

“This caught us completely by surprise — no one has ever seen anything like this before,” said Yvette Cendes, a research associate at the Center for Astrophysics | Harvard & Smithsonian (CfA), and the lead author of the study.

The black hole is spitting out material at an extremely high speed, around half the speed of light. A phenomenon known as a tidal disruption event (TDE) happened years after the black hole ripped the star apart.

“We have been studying TDEs with radio telescopes for more than a decade, and we sometimes find they shine in radio waves as they spew out material while the star is first being consumed by the black hole,” said co-author Edo Berger. “But in AT2018hyz there was radio silence for the first three years, and now it’s dramatically lit up to become one of the most radio-luminous TDEs ever observed.”

Something Out Of The Ordinary

What’s interesting is that scientists had observed this event and found wasn’t anything out of the ordinary. However, this outflow turned out to be very delayed and much faster compared to typical outflows.

“This is the first time that we have witnessed such a long delay between the feeding and the outflow,” Berger says. “The next step is to explore whether this actually happens more regularly and we have simply not been looking at TDEs late enough in their evolution.”

Unraveling Mysteries Of Black Holes

Previously, astronomers successfully detected the light behind the black hole. Why this matters because it corroborates the theory of general relativity by Albert Einstein.

The researchers managed to detect bright flares of x-ray from a black hole that is around 800m light-years away from our planet. These flares were observed while studying a phenomenon known as the corona. The telescope also managed to capture luminous echoes, which were snapped in different colors.