Black hole devours star; intense radiation emitted.
Black holes are mysterious cosmic phenomena that lie in wait, until a hapless star wanders by and gets caught in their gravitational grasp. Astronomers are using NASA’s Hubble Space Telescope to study these violent encounters, known as “tidal disruption events”, in detail. A recent example, the AT2022dsb tidal event, was observed from a galaxy 300 million light-years away. The ultraviolet radiation from the shredded star, including hydrogen, carbon, and more, provide forensic clues to the black hole homicide.
NASA recently reported that they spotted another black hole tidal disruption event on March 1, 2021. Data was collected in X-ray light from an extremely hot corona around the black hole, after the star was already torn apart. Astronomers are excited because this data can provide details about what the debris is doing and tell us a lot about a black hole.
Artist’s illustrations show the sequence of events that occur when a star is devoured by a black hole. A star passes near a supermassive black hole in the center of a galaxy, and its outer gasses are pulled into the black hole’s gravitational field. This causes the star to be shredded as tidal forces pull it apart, and the stellar remnants are pulled into a donut-shaped ring around the black hole. Eventually, the debris falls into the black hole, unleashing a tremendous amount of light and high-energy radiation.
The Hubble spectroscopic data are interpreted as coming from a very bright, hot, donut-shaped area of gas that was once the star. This area, known as a torus, is the size of the solar system and is swirling around a black hole in the middle. Scientists are learning more about this event since they were able to observe it at its early stages.
Changes in the doomed star’s condition take place on the order of days or months, but for any given galaxy with a quiescent supermassive black hole at the center, NASA believes shedding happens only a few times every 100,000 years. Astronomers are learning more about these events as they observe them with ground-based and space-based telescopes, and this knowledge helps us to better understand the mysteries of black holes.