https://phys.org/news/2018-05-massive-black-hole-devours-star.html > In the center of every big galaxy, there is a supermassive black hole, millions to billions times heavier than the Sun. However, it is difficult to observe the majority of them, as they don't emit any light or radiation. This only happens, when some form of material is pulled into the extremely strong gravitational field of the black hole. On rare occasions, actually as rare as once in every 10.000 years for one galaxy, a star passes very close by the supermassive black hole, and the gravity of the black hole tears it apart. This type of fatal event is called a tidal disruption event. > When a tidal disruption event happens, the black hole will be "overfed" with stellar debris for a while. "It is interesting to see how materials get their way into the black hole under such extreme conditions," says Dr. Jane Dai who has led the study. "As the black hole is eating the stellar gas, a vast amount of radiation is emitted. The radiation is what we can observe, and using it we can understand the physics and calculate the black hole properties. This makes it extremely interesting to go hunting for tidal disruption events."