When a black hole swallows a star, it’s big news, and for the first time an international team of astrophysicists, led by a scientist from Johns Hopkins University, has actually witnessed the event. As the super-massive black hole (SMBH) ate the star, it ejected a flare of matter, which was moving nearly at the speed of light.
Last month, we wrote about the SMBH flaring up after it ate a star. Now, a team of astronomers from Johns Hopkins University have followed up on the event in greater detail. In their research, they were able to confirm the previous study, and had expanded on how common tidal disruption flares are.
The star, which was about the size of our Sun, was tracked by the scientists as it shifted from its normal path. The star had slipped into the gravitational pull of the SMBH, where it was then sucked in, said Sjoert van Velzen, a Hubble fellow at Johns Hopkins.
Watch as this artist’s rendering illustrates new findings about a star shredded by a black hole, from NASA Goddard:
“These events are extremely rare,” van Velzen said in a press release. “It’s the first time we see everything from the stellar destruction followed by the launch of a conical outflow, also called a jet, and we watched it unfold over several months.”
According to PHYS.ORG, astrophysicists had predicted that when a black hole is force-fed, a large amount of gas, in this case a whole star, then a fast-moving jet of plasma — elementary particles in a magnetic field — can escape from near the black hole’s rim, or “event horizon.” This study suggests this prediction was correct, the scientists said.
Van Velzen headed the analysis, and had coordinated scientists in the United States, the Netherlands, Great Britain, and Australia. “Previous efforts to find evidence for these jets, including my own, were late to the game,” he said.
“Super-massive black holes, the largest of black holes, are believed to exist at the center of most massive galaxies. This particular one lies at the lighter end of the super-massive black hole spectrum, at only about a million times the mass of our Sun, but still packing the force to gobble a star,” wrote Johns Hopkins.
A team from Ohio State University were the first to discover the star being destroyed, announcing it on Twitter in December 2014. After reading about the discovery, van Velzen contacted a team of astrophysicists from the University of Oxford led by Rob Fender. The team then rushed to follow up on the discovery using radio telescopes, and was just in time to catch the event.
NASA’s swift satellite spots black hole devouring a star by Universe Odyssey:
By the time the event was over, the international team had received data from satellites and ground-based telescopes. By using x-ray, radio, and optical signals, the team had a “multi-wavelength” portrait of the event.
Material, such as gas, dust, and other stellar debris, which is close to the black hole but has not fallen into it (called accretion disks), can also form jets, so the team had to rule this out first. The researchers were able to confirm that the sudden increase of light from the galaxy was due to a newly trapped star.
‘The destruction of a star by a black hole is beautifully complicated, and far from understood,’
Van Velzen said: “From our observations, we learn the streams of stellar debris can organize and make a jet rather quickly, which is valuable input for constructing a complete theory of these events.”
The galaxy where this event had taken place is at least three times closer than any other previously studied — only 300 million light years away (one light year is 5.88 trillion miles). The findings have been published in the journal Science.