New telescope imagery suggests that stars can survive encounters with black holes, a phenomenon that has been modeled but seldom observed, astronomers say.
Using an X-ray telescope orbiting the Earth, astronomers peered 1 billion light-years into deep space and observed black holes partially destroying the same stars over and over, according to the European Space Agency.
“At first, we were absolutely puzzled,” astronomer Thomas Wevers stated in an agency news release. “We had to go back to the drawing board to assess all the possible options to explain the observed behavior.”
When a star veers too close to a black hole, a region in space with inescapably strong gravity, it gets torn apart by “strong tidal forces,” creating stellar debris that the black hole then consumes, the agency stated.
This phenomenon, known as a tidal disruption event, emits a bright flash of light that can be detected via telescope, directing astronomers toward the black holes, which are normally difficult to detect.
The flashes of light, called flares, usually last for several months while a black hole devours a star.
However two new stars have bucked the trend, continuing to shine bright after their first encounter with a black hole, indicating they were not entirely destroyed.
These stars — dimmed but not yet dead — continue to orbit the black hole, creating a pattern of repetitive flares known as a partial tidal disruption event. One of the stars exhibited a new flare roughly every 223 days.
The quick recurrence of flares suggests the stars are encircling the black holes at a very close distance.
Tidal disruption events have been studied for decades by astronomers, according to research published by the Royal Astronomical Society. And partial events, like the two recently observed, have been meticulously simulated.
“It was a very exciting moment when we realized that the model for a repeating tidal disruption event could reproduce the observed data,” Thomas stated.
Astronomers, using a highly sensitive European Photon Imaging Camera, will continue to monitor these stars for partial tidal disruption events. However, there is a chance that the next time they gaze into deep space, they will be met with total darkness, meaning the stars have finally been swallowed whole, the agency stated.